Rare Earth Metals: An Introduction
Austin A Mardon
Sam Zhang
Anittha MappanasingamAnusha A MappanasingamSean Lyeo
Samira Sunderji
Sheher-Bano Ahmed2021, Golden Meteorite Press
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As the reality of anthropogenic climate change bears down on us, a foreboding cloud over our planet’s future, the need for renewable alternatives to fossil fuels becomes more critical. However, our journey to a cooler planet is being hindered by one key player that most people are unaware of: rare earth metals. Making up the lanthanide series in the periodic table, these elements are an integral part of almost all renewable energy technologies, as well as most of the electronic devices we use on a daily basis. They are difficult to find, expensive to refine, and their use can have disastrous environmental impacts. Read on to learn more about rare earth metals: their origins, the politics surrounding their extraction, and much more.
Related papers
Rare Earth Elements: Overview of Mining, Mineralogy, Uses, Sustainability and Environmental Impact
Resources, 2014
Rare earths are used in the renewable energy technologies such as wind turbines, batteries, catalysts and electric cars. Current mining, processing and sustainability aspects have been described in this paper. Rare earth availability is undergoing a temporary decline due mainly to quotas being imposed by the Chinese government on export and action taken against illegal mining operations. The reduction in availability coupled with increasing demand has led to increased prices for rare earths. Although the prices have come down recently, this situation is likely to be volatile until material becomes available from new sources or formerly closed mines are reopened. Although the number of identified deposits in the world is close to a thousand, there are only a handful of actual operating mines. Prominent currently operating mines are Bayan Obo in China, Mountain Pass in the US and recently opened Mount Weld in Australia. The major contributor to the total greenhouse gas (GHG) footprint of rare earth processing is hydrochloric acid (ca. 38%), followed by steam OPEN ACCESS Resources 2014, 3 615 use (32%) and electricity (12%). Life cycle based water and energy consumption is significantly higher compared with other metals.
The rare-earth elements: Vital to modern technologies and lifestyles
Fact Sheet, 2014
Until recently, the rare-earth elements (REEs) were familiar to a relatively small number of people, such as chemists, geologists, specialized materials scientists, and engineers. In the 21st century, the REEs have gained visibility through many media outlets because (1) the public has recognized the critical, specialized properties that REEs contribute to modern technology, as well as (2) China's dominance in production and supply of the REEs and (3) international dependence on China for the majority of the world's REE supply. Since the late 1990s, China has provided 85-95 percent of the world's REEs. In 2010, China announced their intention to reduce REE exports. During this timeframe, REE use increased substantially. REEs are used as components in high technology devices, including smart phones, digital cameras, computer hard disks, fluorescent and light-emitting-diode (LED) lights, flat screen televisions, computer monitors, and electronic displays. Large quantities of some REEs are used in clean energy and defense technologies. Because of the many important uses of REEs, nations dependent on new technologies, such as Japan, the United States, and members of the European Union, reacted with great concern to China's intent to reduce its REE exports. Consequently, exploration activities intent on discovering economic deposits of REEs and bringing them into production have increased.
The Rare Earths in Modern Science and Technology
1982
It was expected that the conference would provide a forum for critical examination and review of the current and important trends in rare earth science and technology. To this end, over 170 papers were presented in both oral and poster sessions by researchers representing some nineteen countries. The program committee was particularly gratified to see the diversity of effort being devoted to rare earth research by different disciplines allover the world. The collection of refereed papers in this volume attests to the fact that the objectives of the program committee were indeed realized.
Rare Earths: Not Rare, But Everywhere
SR Vol.57(07) [July 2020], 2020
Rare Earth Elements: A Review of Production, Processing, Recycling, and Associated Environmental Issues
2013
The U.S. Environmental Protection Agency (EPA) is charged by Congress with protecting the Nation’s land, air, and water resources. Under a mandate of national environmental laws, the Agency strives to formulate and implement actions leading to a compatible balance between human activities and the ability of natural systems to support and nurture life. To meet this mandate, EPA’s research program is providing data and technical support for solving environmental problems today and building a science knowledge base necessary to manage our ecological resources wisely, understand how pollutants affect our health, and prevent or reduce environmental risks in the future The National Risk Management Research Laboratory (NRMRL) is the Agency’s center for investigation of technological and management approaches for preventing and reducing risks from pollution that threaten human health and the environment. The focus of the Laboratory’s research program is on methods and their cost-effectivene...
The Product Chains of Rare Earth Elements
2011
This master thesis will address the topic of rare earth metals and their product chain from early mining processes, through refining to final products and recycling. The analysis will cover the global product chain and its different actors. Rare earth metals consist of 17 elements of the periodic table; the 15 lanthanides, scandium and yttrium. Despite their name, these elements are not rare, but quite abundant all over the earth's crust. Nevertheless, their concentration in the deposits is often very low and they are difficult to extract and refine. The rare earth metals are similar in their characteristics and can be used for many different applications. Rare earths are commonly used in green technology since their unique properties can save weight and increase efficiency in products such as light bulbs, generators in wind power plants, and in different parts of hybrid and electric vehicles. The focus in this report will be on the product chains of the rare earth metals used in permanent magnets and batteries used in hybrid and electric vehicles, these are: neodymium, praseodymium, lanthanum, dysprosium, cerium and terbium. In nature these elements do not occur as metals and many complicated processes are needed to convert them into metals. The product chain starts with the mining and separation processes, next comes further refining and separation processes, and then production of rare earth metals and alloys before they can be shaped into parts in a final product. In total China has more than 95% of the global market for mining and separation processes for rare earth metals, also the production of rare earth metals and alloys occur to a large extent in China. The production of most permanent magnets also takes place in China, but there is also production in Japan, Finland and Germany. Japanese car manufacturers have most of their parts produced within Japanese borders, which means that most permanent magnets used in hybrid and electric vehicles are produced in Japan. The same is true for the NiHM batteries, about 95 % of those that are inside these vehicles today are produced in Japan by Japanese manufacturers. The markets for green technology seem to expand, creating an increasing demand for rare earth metals. To meet the demand with a larger supply there is need for solutions such as new mining projects, reopening of closed mines, or recycling and recovering of rare earths from scrap products and mine tailings. The urge for more supply of rare earth metals and also rising prices presents a good incentive for recycling and recovering different rare earth metals from discarded products. These recycling and recovering processes are technically and often economically very demanding. Today there are processes that could recover rare earths with a high level of purity, but the problem is often the huge costs for the processes as well as handling of waste chemicals and materials that might be toxic. New processes will have to be developed. There has been research for new processes, and recycling/recovering plants are planned to be constructed in Japan as well as other countries. This report will also look at the potential for having parts of the rare earth product chain in Sweden, since the country has both the physical resources and also metallurgical knowledge. With this in mind we discussed the possibilities of eventually operating the processes in the product chain in Sweden, and aspects of this scenario.
Rare earth elements as critical raw materials: Focus on international markets and future strategies
Resources Policy, 2013
Supply of some critical raw materials by European industry is becoming more and more difficult. After the case of natural textile fibres, in particular cotton, and timber, over the last few years the problem of rare earths (REs) availability has also risen. The 97% of the global supply of rare earth metals (REMs) is produced by China, that has recently done copious cuts of its exports, apparently in order to protect its environment. This fact has greatly increased the REs prices, causing tension and uncertainty among the world hi-tech markets. Many of these materials, in fact, have very few effective substitutes and low recycling rates too. In addition, their natural reserves of rare earths are concentrated in a small number of countries (China, Brazil, US, Russia, Democratic Republic of Congo). REMs are a group of 17 elements particularly used in many new electronic and advanced components: such as fuel cells, mobile phones, displays, hi-capacity batteries, permanent magnets for wind power generation, green energy devices, etc. Many analysts foresee much more requests in the next decades.
Understanding Rare Earth Elements as Critical Raw Materials
Sustainability, 2023
The boom in technological advances in recent decades has led to increased demand for rare earth elements (REEs) (also known as rare earth metals) across various industries with wide-ranging industrial applications, including in the clean energy sector, but with some environmental, economic, and social footprint concerns. This paper reviews the complexities of the production, consumption, and reuse or recovery of REEs, presenting current trends in terms of potentials and challenges associated with this. This paper in particular focuses on the supply, demand, and (environmental and economic) sustainability of REEs, as a subset of critical raw materials. It does so via a critical stocktaking of key discussions and debates in the field over the past 15 years up until now, through a thematic analysis of the published and gray (policy) literature with a grounded theory approach. The paper finds that carefully balanced lifecycle sustainability assessments are needed for assessing the respective dimensions of the extraction, processing, and reuse or recovery methods for different types of REE sources and supplies to meet current and future demands. It furthermore diagnoses the need for taking into account some shifts and substitutions among REEs also for reasons of cost and locational supplies for the security of supply. Finally, the paper provides some overall policy recommendations for addressing current problems, with a conceptual framing of the UN Sustainable Development Goals
Are rare earths part of a bright future for lighting and displays?
MRS Bulletin, 2016
Rare earths: Applications and market scenario
chemical weekly, 2021
Rare earths are in limelight in last few years the paper examines the uses and markets, worldwide status of resources future.
RARE EARTH METALS:
AN INTRODUCTION
i
Dr. Austin Mardon, Sheher-Bano Ahmed, Sameen Ali,
Samira Sunderji, Si Cong (Sam) Zhang, Anusha Mappanasingam,
Rishi Mohan, Joonsoo Sean Lyeo, Anittha Mappanasingam,
Pareesa Ali, Ashna Hudani, Amir Ala’a
2021
ii
iii
Copyright © 2021 by Austin Mardon
All rights reserved. This book or any portion thereof may not be reproduced or used in any
manner whatsoever without the express written permission of the publisher except for the
use of brief quotations in a book review or
scholarly journal.
First Printing: 2021
Typeset and Cover Design by Anna Kraemer
ISBN 978-1-77369-535-8
Golden Meteorite Press
103 11919 82 St NW
Edmonton, AB T5B 2W3
www.goldenmeteoritepress.com
iv
CONTENTS
Introduction ............................................................................ 1
Chapter 1 ................................................................................ 3
What are the Rare Earth Metals?
Chapter 2 ...............................................................................17
What are the Origins and Future of Rare Earth Metals?
Chapter 3 .............................................................................. 27
Who Discovered the Rare Earth Metals?
Chapter 4 ...............................................................................37
What is the role of Rare Earth Metals in the World?
Chapter 5 .............................................................................. 47
Why are Rare Earth Metals so Important?
Chapter 6 ...............................................................................57
What is the Status of Rare Earth Metals Today?
Chapter 7 .............................................................................. 67
What Science is Involved in Studying the Rare Earth Metals?
Chapter 8 .............................................................................. 79
What Questions Do We Still Have About Rare Earth Metals?
Chapter 9 .............................................................................. 89
How does Rare Earth Metal Mining Affect the Environment?
Chapter 10 ............................................................................ 97
What Controversy is there surrounding the Rare Earth Metals?
References ............................................................................ 105
vii
INTRODUCTION
This book was created through the Antarctic Institute of Canada as a project sponsored by the Government of Canada’s innovative Work-Integrated
Learning program, Level Up. The Antarctic Institute of Canada is a non-profit
Canadian charity organization founded in 1985 by former Antarctic researcher
Austin Mardon. Its original aim was to lobby for the federal government of
Canada to increase the extent of Canadian research in the Antarctic. Today, its
objectives also include supporting scholarly research and academic writing.
A group of twelve postsecondary students worked on this book over a period
of seven days. Each chapter was written by a different student, with some
chapters being created through the collaborative efforts of multiple authors.
All editing, graphic design, and audiobook production was also carried out
by postsecondary students.
Thank you for picking this book up to learn more about rare earth metals.
1
WHAT ARE THE RARE
EARTH METALS?
Written By Sameen Ali
Introduction
Rare earth metals are a set of seventeen metallic elements that are located in
the center of the periodic table with atomic numbers 21, 39, and 57-71 (Eddleman, 2020). These include the fifteen lanthanides, in addition to scandium
and yttrium (Eddleman, 2020). These metals have unusual f luorescent,
conductive, and magnetic properties which make them useful when mixed
with other metals—more specifically in mixtures with metals such as iron
(Eddleman, 2020). Despite their name, the rare earth metals are not especially rare (Eddleman, 2020). These metals can be found all around the globe,
and some of them are just as abundant as copper or tin are in the earth’s
crust (Merril, 2020). However, rare elements are never found in very high
concentrations and are usually found mixed together with one another or
other radioactive elements such as uranium and thorium (Eddleman, 2020).
The chemical properties of the rare elements make them difficult to purify
and extract from such mixtures (Eddleman, 2020). The process is long and
requires a great deal of harmful waste to extract just small amounts of rare
earth metals. These wastes include radioactive water, toxic f luorine, and
acids (Eddleman, 2020).
To further understand the uses and importance of these metals, it is essential
to look into the properties and description of each of these seventeen elements.
3
RaRe eaRth Metals: an IntRoductIon
Sameen Ali
To start with, rare earth metals are categorized into two categories: light
or heavy (Natural Resources Canada, 2021). The former category includes:
lanthanum, cerium, praseodymium, neodymium, promethium, samarium,
europium, gadolinium and scandium, while the latter includes: terbium,
dysprosium, holmium, erbium, thulium, ytterbium, lutetium and yttrium
(Natural Resources Canada, 2021). The light metals are produced in global
abundance and can be supplied easily while the heavy metals are produced
mainly in China and are in limited supply (Natural Resources Canada, 2021).
Let’s discuss each metal and examine the details of each of these seventeen
unique metals.
It is named after the asteroid, Ceres, which in turn was named after the Roman
goddess of agriculture. It belongs to group 5 and has an atomic number of
58 (Royal Society of Chemistry, 2021). It is solid at room temperature with a
melting point of 799ºC and boiling point of 3443ºC (Royal Society of Chemistry,
2021). Cerium has a density of 6.77 g/cm3 with a relative atomic mass of 140.116
amu (Royal Society of Chemistry, 2021). Cerium is a grey metal and is not
widely used due to its ability to easily tarnish and react with water and burn
when heated (Royal Society of Chemistry, 2021). Thus, it is one of the most
reactive rare-earth metals and is also very malleable (Staff, 2013). Cerium
can oxidize at room temperature and decomposes slowly in cold water and
extremely rapidly in hot water (Staff, 2013). If cerium is put in an alkaline
solution, dilute and concentrate it will dissolve. This metal is the most abundant out of the lanthanides (Staff, 2013). It is more abundant than tin or lead
and almost as abundant as zinc. It can be found in various minerals such as
bastnaesite and monazite (Royal Society of Chemistry, 2021). Cerium oxide is
produced by heating bastnaesite ore, and treating it with hydrochloric acid.
Metallic cerium can be obtained by heating cerium (III) f luorine with calcium
or by the electrolysis of molten cerium oxide. Similar to lanthanum, cerium
has no biological functions (Royal Society of Chemistry, 2021).
The Light Rare Earth Metals
Lanthanum
Lanthanum was discovered in 1839 by Carl Gustav Mosander, its name is
derived from the greek ‘lanthanein’ meaning to lie hidden (Royal Society of
Chemistry, 2021). Although the metal itself has no commercial use, when
combined with other metals to form an alloy, it can have many uses. Such uses
will be further discussed in Chapter 4. The metal appears soft and silverywhite. It rapidly tarnishes in air and burns easily when ignited (Royal Society
of Chemistry, 2021). This metal belongs to group 4 and has an atomic number
of 57 on the periodic table. At room temperature (23ºC) it is in a solid state
(Royal Society of Chemistry, 2021). Lanthanum has a melting point of 920ºC
and a boiling point of 3464ºC with a density of 6.15 g/cm3 and a relative atomic
mass of 138.905 (Royal Society of Chemistry, 2021). This metal does not have
any biological role. In addition, the element and its compounds are moderately toxic. Lanthanum is found mainly in monazite deposits, which contain
25 percent of lanthanum, and bastnaesite which contains 38 percent of the
metal (Royal Society of Chemistry, 2021). Techniques such as ion-exchange
and solvent extraction are used to isolate the rare earth elements from such
minerals. Lanthanum metal is usually obtained by reducing anhydrous
f luoride with calcium (Royal Society of Chemistry, 2021).
Cerium
Cerium was discovered in 1803 by Jons Jacob Berzellius and Wilhelm Hisinger,
4
Praseodymium
Praseodymium was discovered in 1885 by Carl Auer von Welsbach, its name was
derived from the Greek ‘prasios didymos’ meaning green twin. It also belongs
to group 6 with an atomic number of 59 (Royal Society of Chemistry, 2021).
Praseodymium has a melting point of 931ºC and a boiling point of 3520ºC with
a density of 6.77 g/cm3 and an atomic mass of 140.908 amu (Royal Society of
Chemistry, 2021. In appearance, the metal is soft and silvery. Praseodymium
has low toxicity and occurs along with other lanthanide elements in a variety
of minerals (Royal Society of Chemistry, 2021). The two principal sources of
praseodymium are once again monazite and bastnasite (Royal Society of
Chemistry, 2021). It is extracted from these minerals by ion exchange and
solvent extraction. Praseodymium metal is prepared by reducing anhydrous
chloride and calcium (Lenntech, n.d). It is also very malleable and is able to
react with oxygen (Lenntech, n.d). As a result, when it is exposed to air it forms
5
RaRe eaRth Metals: an IntRoductIon
Sameen Ali
a green oxide, which does not protect it from further oxidation. Praseodymium
is also more resistant to corrosion in air than other rare metals; however, it
still requires proper storage under oil or coated with plastic. Praseodymium
can also react rapidly with water (Lenntech, n.d).
radioactive metal. Promethium emits beta radiation—making it very rare
since it is a radioactive metal (Lenntech, n.d). Hence, it is difficult to study,
and its chemical and physical properties are not well-defined (Lenntech,
n.d). Promethium salts have a pink or red colour that tints the surrounding
air with a pale blue-green light. Its longest lived isotope has a half-life of 18
years (Royal Society of Chemistry, 2021). For this reason it cannot be found
naturally on Earth and instead has been found on a star in the Andromeda
galaxy which presumably created this metal through unknown chemical
processes (Royal Society of Chemistry, 2021). . Promethium can be produced
by irradiating neodymium and praseodymium with neutrons, deuterons and
alpha particles. It can also be prepared by ion exchange of nuclear reactor fuel
processing wastes (Royal Society of Chemistry, 2021).
Neodymium
Neodymium was discovered in 1885 by Carl Auer von Welsbach, Its name is
derived from the Greek ‘neos didymous’ meaning new twin. It is a part of
group 7 and has an atomic number of 60 (Royal Society of Chemistry, 2021).
Neodymium has a melting point of 1016ºC and a boiling point of 3074ºC (Royal
Society of Chemistry, 2021). Its density is 7.01 g/cm3 with a relative atomic mass
of 144.242 (Royal Society of Chemistry, 2021). Neodymium is solid at room
temperature and appears as a silvery white metal which rapidly tarnishes in
air. It is moderately toxic and irritating to the eyes (Royal Society of Chemistry,
2021). Similar to other rare earth metals, the main sources of neodymium
are the minerals monazite and bastnaesite (Royal Society of Chemistry,
2021). Neodymium can be extracted from these minerals by ion exchange
and solvent extraction (Royal Society of Chemistry, 2021). The metal can also
be obtained by reducing anhydrous neodymium chloride or f luoride with
calcium (Royal Society of Chemistry, 2021). This metal is incredibly reactive
and quickly tarnishes in air, and the coated form does not protect the metal
from further oxidation, so it must be stored away from contact with oxygen
(Lenntech, n.d). Just like praseodymium it slowly reacts with cold water and
rapidly reacts with hot water (Lenntech, n.d).
Promethium
Promethium was discovered in 1945 by Jacob A. Marinsky, Lawrence E.
Glendenin, and Charles D. Coryell, It is named after Prometheus of Greek
mythology who stole fire from the Gods and gave it to humans (Royal Society
of Chemistry, 2021). This metal is part of group 8, with an atomic number
of 61. It has a melting point of 1042ºC and a boiling point of 3000ºC with a
density of 7.26 g/cm3 and a relative atomic mass of 145 amu (Royal Society
of Chemistry, 2021). Promethium is a solid at room temperature and is a
6
Samarium
Discovered in 1879 by Paul-Émile Lecoq de Boisbaudran, the name is derived
from samarskite, the name of the mineral from which it was first isolated.
This metal belongs to group 9 with an atomic number of 62 (Royal Society of
Chemistry, 2021). Samarium has a melting point of 1072ºC and a boiling point
of 1794ºC with a density of 7.52 g/cm3 and relative atomic mass of 150.36 amu
(Royal Society of Chemistry, 2021). In appearance, Samarium is silvery-white
(Royal Society of Chemistry, 2021). At room temperature, it is relatively stable;
however, it ignites when heated above 150ºC and forms an oxide coating in
moist air (Lenntech, n.d). Similar to europium, samarium has a relatively
stable oxidation state (II) (Lenntech, n.d). Although samarium has no biological
roles, it has been noted to stimulate metabolism. Soluble samarium salts are
mildly toxic, and if ingested, there are health hazards that can apply (Lenntech, n.d). Exposure to samarium causes sinus and eye irritation (Lenntech,
n.d). Just like the other rare earth metals so far, samarium can be found in
several minerals, the principal ones being monazite and bastnaesite (Royal
Society of Chemistry, 2021). It is separated from the other components of the
mineral by ion exchange and solvent extraction (Royal Society of Chemistry,
2021). Recently, electrochemical deposition has been used to separate samarium from other lanthanides (Royal Society of Chemistry, 2021). A lithium
7
RaRe eaRth Metals: an IntRoductIon
Sameen Ali
citrate electrolyte is used and a mercury electrode. Samarium can also be
produced by reducing the oxide from electrode with barium (Royal Society
of Chemistry, 2021).
Chemistry, 2021). This metal reacts slowly in water and dissolves in acids. It
can become superconductive below 809.85ºC (Lenntech, n.d). It is strongly
magnetic at room temperature (Lenntech, n.d). Gadolinium, similar to the
other lanthanides, forms compounds of low to moderate toxicity (Lenntech,
n.d). Gadolinium salts irritate skin and eyes and are suspected to create tumors
(Lenntech, n.d). However, gadolinium toxicity has not been investigated in
detail (Lenntech, n.d). Just like other lanthanides, gadolinium is mainly found
in the minerals monazite and bastnaesite (Royal Society of Chemistry, 2021).
It can be commercially prepared from these minerals by ion exchange and
solvent extraction (Royal Society of Chemistry, 2021). It is also prepared by
reducing anhydrous gadolinium f luoride with calcium metal (Royal Society
of Chemistry, 2021).
Europium
Europium was discovered in 1901 by Eugène-Anatole Demarçay and is named
after Europe. It also belongs to period 6 on the periodic table with an atomic
number of 63 (Royal Society of Chemistry, 2021). The metal has a melting
point of 822ºC and a boiling point of 1529ºC. It has a density of 5.24 g/cm3
with a relative atomic mass of 151.964 amu(Royal Society of Chemistry, 2021).
Europium appears to be soft and is a silver metal which tarnishes quickly in
air at room temperature and reacts with water (Lenntech, n.d). It is one of
the most expensive rare earth metals and also the most reactive from the
lanthanide group (Lenntech, n.d). burns at about 150ºC to 180ºC and can react
readily with water (Lenntech, n.d). Europium has no biological role, however
europium salt can be mildly toxic by ingestion; however, its toxicity is yet to
be fully investigated (Lenntech, n.d). Just like other lanthanides, europium
is mainly found in the minerals monazite and bastnaesite (Lenntech, n.d). It
can be prepared from these minerals using the same techniques discussed as
the other rare metals(Royal Society of Chemistry, 2021). However, the most
common method for preparation is by heating europium (III) oxide with an
excess of lanthanum under a vacuum (Royal Society of Chemistry, 2021).
Gadolinium
Gadolinium was discovered in 1880, which was named in honour of Johan
Gadolin, who discovered this metal (Royal Society of Chemistry, 2021). This
will be further discussed in chapter 3. The metal is part of group 11 with an
atomic number of 64 (Royal Society of Chemistry, 2021). Gadolinium has a
melting point of 1313ºC and a boiling point 3273ºC with a density of 7.9 g/
cm3 and a relative atomic mass of 157.25 amu (Royal Society of Chemistry,
2021). In appearance, gadolinium is a soft, silvery, ductile metal that reacts
with oxygen and water (Royal Society of Chemistry, 2021). The metal does
not tarnish in dry air but an oxide film forms in moist air (Royal Society of
8
Scandium
Scandium was discovered in 1879 by Lars Frederik Nilson. The name is derived
from ‘Scandia’, the Latin name for Scandinavia. This metal is part of period 4
and has a melting point of 1541ºC and a boiling point of 2836ºC with a density
of 2.99 g/cm3 (Royal Society of Chemistry, 2021). It has a relative atomic
mass of 44.956 amu (Royal Society of Chemistry, 2021). Scandium is a silvery
metal that tarnishes in air, burns easily and reacts with water (Royal Society
of Chemistry, 2021). The metal develops a slightly yellowish or pinkish cast
when exposed to air (Royal Society of Chemistry, 2021). Scandium easily gets
tarnished in air and burns easily once it has been ignited. It reacts with water
to form hydrogen gas and will dissolve many acids (Lenntech, n.d). Pure scandium is produced by heating scandium f luoride (ScF3) with calcium metal
(Lenntech, n.d). Scandium is very widely distributed and occurs in minute
quantities in over 800 mineral species. It is the main component of the very
rare and collectable mineral thortveitite, found in Scandinavia (Lenntech,
n.d). The metal can also be recovered as a by-product from uranium mill
tailings (sandy waste material) (Royal Society of Chemistry, 2021). In addition,
it can be prepared by electrolysing molten potassium, lithium and scandium
chlorides, using electrodes of tungsten wire and molten zinc (Royal Society
of Chemistry, 2021).
9
RaRe eaRth Metals: an IntRoductIon
The Heavy Rare Earth Metals
Terbium
Terbium was discovered in 1843 by Carl Gustav Mosander, and is named after
Ytterby, Sweden (Royal Society of Chemistry, 2021). It belongs to group 12 on
the periodic table and has an atomic number of 65 (Royal Society of Chemistry, 2021). It has a melting point of 1359ºC and boiling point of 3230ºC with a
density of 8.23 g/cm3 and relative atomic mass of 158.925 amu (Royal Society
of Chemistry, 2021). In appearance, terbium is a soft, silvery metal. Terbium
is a malleable, ductile member of the lanthanide group of the periodic table.
It is reasonably stable in air, but it slowly oxidises and it reacts with cold
water (Lenntech, n.d). Although terbium has no biological role, it may be
mildly toxic by ingestion (Lenntech, n.d). Terbium powder and compounds
are very irritating if they come into contact with the skin and eyes (Lenntech, n.d). However, similar to other rare earth metals, its toxicity is yet to
be investigated in greater detail (Lenntech, n.d). Terbium can be recovered
from minerals such as monazite and bastnaesite by ion exchange and solvent
extraction (Lenntech, n.d). It is also obtained from euxenite, a complex oxide
which contains around 1% terbium (Lenntech, n.d). The metal is usually
produced commercially by reducing anhydrous f luoride or chloride with
calcium metal, under a vacuum (Lenntech, n.d). It is also possible to obtain
this metal by electrolysis of terbium oxide in molten calcium chloride (Royal
Society of Chemistry, 2021).
Dysprosium
Dysprosium was discovered in 1886 by Paul-Émile Lecoq de Boisbaudran, Its
name is derived from the Greek ‘dysprositos’, meaning hard to get. It belongs
in group 13 of the periodic table, with an atomic number of 66 (Royal Society
of Chemistry, 2021). It has a melting point of 1412ºC and a boiling point of
2567ºC with a density of 8.55 g/cm3 and an atomic mass of 162.5 amu (Royal
Society of Chemistry, 2021). In appearance, it is a bright, silvery, metallic
element (Royal Society of Chemistry, 2021). It is also lustrous and very soft
(Lenntech, n.d). It is stable in air at room temperature, although it is slowly
oxidized by oxygen (Lenntech, n.d). It reacts with cold water and rapidly
dissolves in acids (Lenntech, n.d). It forms several brightly coloured salts
10
Sameen Ali
(Lenntech, n.d). Dysprosium’s characteristics can be strongly affected by
the presence of impurities (Lenntech, n.d). Dysprosium has no biological
role; however, soluble dysprosium salts are mildly toxic by ingestion, while
insoluble salts are non toxic (Lenntech, n.d). Tests done on mice have shown
that a dose of 500 grams or more of soluble dysprosium salts would be needed
to put an individual's life at risk (Lenntech, n.d). Just like other rare earth
metals, dysprosium is found in the minerals monazite and bastnaesite (Royal
Society of Chemistry, 2021). It is also found in smaller quantities in several
other minerals such as xenotime and fergusonite (Royal Society of Chemistry,
2021). It can be extracted from these minerals by ion exchange and solvent
extraction. It can also be prepared by the reduction of dysprosium trif luoride
with calcium metal (Royal Society of Chemistry, 2021).
Holmium
Holmium was discovered in 1878 by Marc Delafontaine and Louis Soret. Its
name is derived from the Latin name for Stockholm, ‘Holmia’ (Royal Society
of Chemistry, 2021). Holmium belongs to group 14 of the periodic table and
has an atomic number of 67 (Royal Society of Chemistry, 2021). Its melting
point is 1472ºC and boiling point is 2700ºC with a density of 8.8 g/cm3 and an
atomic mass of 164.930 amu (Royal Society of Chemistry, 2021). Holmium is a
malleable, soft, lustrous metal and has a silvery surface (Lenntech, n.d). It can
be slowly worn down by oxygen and water and dissolves in acids (Lenntech,
n.d). It is stable in dry air at room temperature. Holmium has no known
biological roles and is non-toxic (Royal Society of Chemistry, 2021). It can
be found as a minor compound of the minerals monazite and bastnaesite
(Royal Society of Chemistry, 2021). It is extracted from those ores that are
processed to extract yttrium. It can also be obtained by ion exchange and
solvent extraction (Royal Society of Chemistry, 2021).
Erbium
Erbium was discovered in 1843 by Carl Gustav Mosander, and is named after
Ytterby, Sweden. It belongs to period 6 on the periodic table and has an
atomic number of 68 (Royal Society of Chemistry, 2021). Its melting point is
1529ºC and boiling point is 2868ºC (Royal Society of Chemistry, 2021). It has
11
RaRe eaRth Metals: an IntRoductIon
Sameen Ali
a density of 9.07 g/cm3 with a relative atomic mass 167.259 amu (Royal Society
of Chemistry, 2021). Erbium is a soft, silvery, metallic element (Royal Society
of Chemistry, 202). In addition, it is malleable, lustrous and is very stable
in air. It reacts very slowly with oxygen and water and is able to dissolve in
acids (Lenntech, n.d). Its salts are rose colored and the gas produces a sharp
absorption spectrum in visible, ultraviolet and infrared light (Lenntech,
n.d). Erbium is found principally in minerals like monazite and bastnaesite
(Royal Society of Chemistry, 2021). In addition, it can also be extracted by ion
exchange and solvent extraction (Royal Society of Chemistry, 2021).
monazite. It can be extracted by ion exchange and solvent extraction (Royal
Society of Chemistry, 2021).
Thulium
Thulium was discovered in 1879 by Per Teodor Cleve, the name comes from
Thule, the ancient name for Scandinavia (Royal Society of Chemistry, 2021).
It is a part of group 16 with an atomic number of 69 (Royal Society of Chemistry, 2021). It has a melting point of 1545ºC and a boiling point of 1950ºC
with a density of 9.32 g/cm3 and an atomic mass of 168.934 amu (Royal Society of Chemistry, 2021). Thulium is a bright, silvery metal (Royal Society
of Chemistry, 2021). It has no biological roles and is non-toxic. Thulium is
found principally in the mineral monazite, which contains about 20 parts per
million (Royal Society of Chemistry, 2021). It is extracted by ion exchange and
solvent extraction (Royal Society of Chemistry, 2021). The metal is obtained
by reducing the anhydrous f luoride with calcium, or reducing the oxide with
lanthanum (Royal Society of Chemistry, 2021).
Ytterbium
Ytterbium was discovered in 1878, it is named after Ytterby, Sweden (Royal
Society of Chemistry, 2021). This metal belongs to group 17 on the periodic
table and has an atomic number of 70 (Royal Society of Chemistry, 2021). Its
melting point is 824ºC and boiling point is 1196ºC. It has a density of 9.6 g/
cm3 with an atomic mass of 173.045 amu (Royal Society of Chemistry, 2021).
Ytterbium is a soft, silvery metal which slowly oxidises in air, forming a
protective surface layer (Royal Society of Chemistry, 2021). This metal has
no biological role and has low toxicity (Royal Society of Chemistry, 2021).
Just like several other rare earth metals, it is primarily found in the mineral
12
Lutetium
Lutetium was discovered in 1907 by Charles James. Its name was derived from
the Romans’ name for Paris, ‘Lutetia’. It belongs to group 18 on the periodic
table and has an atomic number of 71 (Royal Society of Chemistry, 2021). Its
melting point is 1663ºC and boiling point is 3402ºC with a density of 9.84 g/
cm3 and an atomic mass of 174.967 amu (Royal Society of Chemistry, 2021).
Lutetium is silvery-white, hard and dense. It has no biological role and has
low toxicity (Royal Society of Chemistry, 2021). Just like any other rare earth
metal its most common source is the mineral monazite (Royal Society of
Chemistry, 2021). It is extracted with difficulty, by reducing the anhydrous
f luoride with calcium metal (Royal Society of Chemistry, 2021).
Yttrium
Yttrium was discovered in 1794 and is named after Ytterby, Sweden since the
element was first discovered there. It belongs to group 3 on the periodic table
and has an atomic number of 39 (Royal Society of Chemistry, 2021). It has a
melting point of 1522ºC and a boiling point of 3345C with a density of 4.47 g/
cm3 and a relative atomic mass of 88.906 amu (Royal Society of Chemistry,
2021). Yttrium is a soft, silvery metal and has no biological uses. Its soluble
salts are mildly toxic (Royal Society of Chemistry, 2021). In terms of natural
abundance, the mineral xenotime contains up to 50% yttrium phosphate (Royal
Society of Chemistry, 2021). It is mined primarily in China and Malaysia (Royal
Society of Chemistry, 2021). Yttrium also occurs alongside other rare earth
minerals, in monazite and bastnasite (Royal Society of Chemistry, 2021). The
metal can also be produced by yttrium f luoride using calcium metal (Royal
Society of Chemistry, 2021).
Conclusion
These seventeen rare earth metals each have unique properties and roles.
These roles are further discussed in chapter three. Each metal is unique yet
there are some similarities between them. Although some of these metals are
13
RaRe eaRth Metals: an IntRoductIon
difficult to extract, they are worth the challenge to obtain in order to fulfill
their roles. In addition, it is evident that these elements have many similarities
amongst them. These seventeen metals make up the center of the periodic
table and are essential to our modern world, with its reliance on electronic
devices. Many questions regarding these seventeen metals remain, such as
where these rare earth metals come from. The next chapter will try to answer
this question and provide a more thorough understanding of these metals.
14
WHAT ARE THE ORIGINS
AND FUTURE OF RARE
EARTH METALS?
Written By Samira Sunderji
Introduction
Rare earth metals hold a unique place among the elements on the periodic
table as they serve as integral components of various electronic devices and
clean energy resources (Elliot, 2013). Although these rare metals are very
much alike chemically and physically, their magnetic properties, temperature
resistance, and resistance to corrosion are what sets them apart from each
other (Elliot, 2013). Regardless, they are essential to our modern lives.
While rare earth metals play an important role in a number of scientific discoveries and applications, their origins and histories are equally as important
to understand. This information proves to be useful to create a framework
for scientists and companies to understand rare earth metals, so that their
use can be expanded.
These metals, as you will see throughout this book, hold significant scientific
and geopolitical importance (History and Future of Rare Earth Elements,
2020). The status and power dynamics between countries continue to shift in
regard to rare earth metal production. This is largely due to the low concentrations and small deposits of rare earth metals on the surface of the Earth,
in comparison to the abundance of these elements within the Earth’s crust.
Despite the revenue these elements produce in countries where mining and
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RaRe eaRth Metals: an IntRoductIon
Samira Sunderji
production processes continue, one particular concern for various activists
is the effect these processes have on the environment. Therefore, sustainable
practices and technologies for rare earth metal extractions are being developed
and implemented. Nonetheless, the unique properties of rare earth metals are
what make them valuable and they will remain an integral part of our future.
these elements are never found in extremely high concentrations and are
usually found mixed together with one another or with radioactive elements,
such as uranium and thorium (Long et al., 2010). Consequently, most of the
world’s supply of rare earth metals come from only a handful of sources and
refining these minerals into individual elements takes many days of heavy
processing.
While the previous chapter detailed the properties of all 17 rare earth metals,
this chapter will elaborate on the rarity of these elements, their origins,
countries involved in extraction and production, as well as possible future
applications and uses of rare earth metals.
Are These Metals Really ‘Rare’?
As stated earlier, rare earth metals are composed of 17 metallic elements.
On the periodic table, these elements have the atomic numbers 21, 39, and 57
through to 71 (History and Future of Rare Earth Elements, 2020). The atomic
number of these elements describe the number of protons and neutrons of
an atom, and this determines the chemical properties of the element and its
place on the periodic table.
Geologically speaking, rare earth metals are not as rare as they seem and
the term ‘rare’ earth metals is a historical misnomer; small deposits of these
metals are found all over the globe. For example, thulium and lutetium,two
of the least abundant rare earth elements however, are nearly 200 times more
common than gold (Long et al., 2010). On the other hand, some of the more
common and abundant rare earth metals are similar in crustal concentration to common industrial metals such as chromium, nickel, copper, zinc,
tin, and lead (Long et al., 2010). The estimated average concentration of rare
earth metals within the Earth’s crust ranges from approximately 150 to 220
parts per million (Long et al., 2010). This is in contrast to other metals that
are mined on an industrial scale such as copper (55 parts per million) and zinc
(70 parts per million) (Long et al., 2010). Due to the process of accretion, rare
earth metals are largely found in the inner parts of the planet (Long et al.,
2010). They concentrate on the surface only in places where eruptions have
occurred causing the metals to work their way up to the Earth’s crust. Thus,
18
How are Rare Earth Metals Created?
Obviously, rare earth metals did not form spontaneously or appear out of thin
air. There are a number of plausible explanations as to how these elements formed.
Nucleosynthesis
An atom is the basic unit of a chemical element. Protons (positively charged
particles) and neutrons (neutrally charged particles) are the key components
that make up an atom’s nucleus. Thus, nucleosynthesis is a process by which
new atomic nuclei are constructed from existing protons and neutrons. The
first known existence of this process is attributed to the Big Bang, during
which light elements such as hydrogen, lithium and helium were formed. These
light elements eventually coalesced (combined and formed) into the earliest
stars. Once hydrogen and helium stars became large enough, heavier elements
were then formed via a process termed stellar nucleosynthesis in which
nuclear fusion at the centre of stars resulted in the creation of these heavier
elements. The process of stellar nucleosis continues to this day. However, a
rarer process, supernova nucleosynthesis, occurs within exploding stars and
is responsible for creating a number of elements we see on the periodic table,
including the rare earth metals.
Sir Fred Hoyle and the Development of Supernova Nucleosynthesis
Born in Yorkshire, England in 1915, Sir Fred Hoyle was a renowned mathematician and physicist, and was particularly known for his involvement in the
development of scientific theories; some of which include steady-state universe
theory as well as the theory of supernova nucleosynthesis (Pontius, 2018). It
was previously thought that even the largest starts did not have high enough
core temperature or pressure to fuse iron into heavier elements. However,
19
RaRe eaRth Metals: an IntRoductIon
Samira Sunderji
in 1954, Hoyle discovered that there is a general tendency for stars of higher
temperatures to become “breeding grounds” for atoms of large atomic weights.
When a star runs out of nuclear fuel (lighter nuclei) and can no longer undergo
fusion reactions, gravity causes the star to collapse. Rapid gravitational shrinkage results in the rapid heating of the star, which in turn generates optimal
conditions for heavier elements to be created through a phenomenally large
explosion—a supernova. The explosion of the star momentarily generates
high enough temperatures and pressures to cause nuclear fusion reactions.
Elements heavier than iron ( Z = 26) are made primarily through supernova
nucleosynthesis—this includes all of the rare earth metals.
important roles in clean energy and high-tech industries, which have placed
them in the spotlight due to the recent popularity of electric vehicles. As will
be discussed in other chapters, China has dominated the rare earth metal
industry and used its economic and political power to leverage other countries (Pistilli, 2021). Other countries that partake in rare earth metal mining
and production include the United States, Myanmar, Australia, Madagascar,
India, Canada, Russia, Thailand, and Brazil (Pistilli, 2021).
Hoyle’s groundbreaking work was built upon the earlier discoveries made by
William Fowler, an American nuclear astrophysicist who won the Nobel Prize
for Physics in 1983 for his role in formulating the widely accepted theory of
element generation (Pontius, 2018). Hoyle’s work filled in gaps in this theory,
enlightening others in the scientific community and explaining the origins
of heavier elements.
Nuclear Fission
Nuclear fission is a process by which the nucleus of an atom is split into two
(or more) smaller nuclei—these are known as fission products. Nuclear fission
occurs with heavier elements when the electromagnetic forces pushing the
nucleus apart dominate over the strong nuclear force holding it together. The
fission of heavy elements on the periodic table is an exothermic reaction, a
reaction that releases energy to its surrounding environment.
How and Where can Rare Earth Metals be Found?
Please note that the countries listed below were the top 10 countries that
mined the most rare earth metals according to data collected by the United
States Geological Survey as of 2020 (Pistilli, 2021).
Rare earth metal production continues to rise across the globe to meet the
demand created by the heightened popularity of renewable energy and newer
technologies. Rare earth metals such as neodymium and praseodymium serve
20
As we know, rare earth metals rarely exist naturally in a pure form. According
to the USGS Rare Earths Report, the principal sources of rare earths are the
minerals bastnasite, monazite, and loparite (Lessar, 2018). Geochemical exploration is the main method of rare earth metal mining. XRF technology and
portable XRF instruments are useful tools to qualitatively and quantitatively
evaluate rare earth metals (Lessar, 2018). XRF stands for X-ray f luorescence
spectroscopy (Lessar, 2018). It is a non-destructive analytical technique used to
determine the elemental composition of materials. Portable XRF instruments
can provide real-time, on-site assays of rare earth metals and other elements
within a geological sample.
The history of global rare earth metal production as well as the role of rare
earth metals in creating power dynamics will be thoroughly discussed in the
coming chapters.
What is the Future of Rare Earth Metals?
As stated previously, rare earth elements are likely to remain an important
part of our future. From their use in medicine to quantum computing and
material sciences, these elements are essential in a variety of contexts. The
role of rare earth metals in clean energy efforts and curbing greenhouse-gas
emissions is especially important to avoid the devastating consequences of
climate collapse. Ongoing processes to decrease the production of internal
combustion cars and increase the production of electric vehicles will also
increase the demand for rare earth metals. The growth of wind farms as a
method of sustainable energy will continue to drive the demand for neodymium and dysprosium, which are used in wind turbine motors. To meet future
21
RaRe eaRth Metals: an IntRoductIon
Samira Sunderji
demands for these elements, minings companies have proposed opening new
mines and building processing plants across the globe. While the ideas behind
these proposals may seem far-fetched and unattainable at this moment in
time, they could become economically viable and a reality if a large increase
in rare earth metal demand increases prices, or if global governments collaborate and subsidize the costs of production, or if climate change becomes so
devastating that we are forced to take action.
drives, and audio devices (Pozo-Gonzalo, 2021). The salt-based systems used
to recover rare earth metals are highly stable which allows for the recovery of
elements such as neodymium without the generation of side products that
can affect the purity of the element (Pozo-Gonzalo, 2021). Unlike previously
reported methods, IFM can recover neodymium metal without a temperature-controlled atmosphere, and can work at temperatures lower than 100oC
(Pozo-Gonzalo, 2021). At this moment in time, IFM has proof of concept at lab
scale and are hoping to scale up the process to be used more widely across the
globe (Pozo-Gonzalo, 2021). In time, this method, along with several others
in the planning and proposal stages, could reduce the need to mine for rare
earth metals,preventing yet another generation of being subjected to toxins
and harmful wastes. Research, such as this, is an important early step towards
establishing a clean and sustainable processing route for rare earth metals.
As rare earth metals cannot be artificially created without a costly associated
process and a low yield, and as increasing demands limit global supplies,
companies and scientists are urgently trying to find ways to recover these
metals. As previously stated, rare earth metals are currently mined or recovered via e-waste recycling (Pozo-Gonzalo, 2021). However, the drawbacks of
these processes include high costs, environmental damage, pollution, and
risk to human safety (Pozo-Gonzalo, 2021). Moreover, to combat the expected
and predicted shortages of rare earth metals, car makers are redesigning
vehicles to use smaller amounts of rare earth metals. Electronic companies
could follow this path and could redesign consumer electronics to be more
easily repaired and upgraded rather than simply discarded. Research into
methods to recover rare earth metals from electronic waste could reduce the
amount of metals that need to be produced by mining. With that being said,
the Institute for Frontier Materials (IFM), in collaboration with a research
center in Spain, have developed a method to utilize environmentally friendly
chemicals to recover rare-earth metals. This involves the process of electrodeposition, in which a low electric current causes the metals to deposit on a
desired surface (Pozo-Gonzalo, 2021). This can alleviate the pressure on the
global supply and reduce our reliance on mining. Electrodeposition is already
used to recover other metals; the improvement of this new method is that it
is sustainable and environmentally friendly through the use of salt-based
(ionic liquid) systems (Pozo-Gonzalo, 2021). The IFM focused on recovering
neodymium, an important rare earth metal with unique magnetic properties
(Pozo-Gonzalo, 2021). Neodymium is in extremely high demand and can be
found in electric motors of cars, mobile phones, wind turbines, hard disk
22
One looming concern for the future of rare earth metals focuses on China’s role
as the largest producer of rare earth metals (History and Future of Rare Earth
Elements, 2020). Planning documents reveal that the Chinese government is
interested in reducing the local pollution and harms caused by manufacturing
and mining rare earth metals (History and Future of Rare Earth Elements,
2020). It is predicted that China may use its investments across the rare earth
metals industry and move to locations outside of China which are under
Chinese financial control) and thus, relocate the pollution to poorer and less
developed countries—from an environmental perspective, this is still a large
concern (History and Future of Rare Earth Elements, 2020).
As a solution to these challenges, governments, activist groups, and companies could collaborate to collect wastes containing rare earths to enable more
economically viable recycling programs. However, matters of sustainability
and socially fair production of these elements largely depend on the willingness of consumers and manufacturers to pay more for materials that are
produced ethically and legally. Additionally, individuals within and outside of
governments must ensure that sustainable production methods are actually
implemented.
23
RaRe eaRth Metals: an IntRoductIon
Conclusion
Rare earth metals form the largest chemically coherent group within the
periodic table. Though generally unfamiliar compared to its popular elemental counterparts (such as hydrogen and helium), the rare earth metals are
an essential component of hundreds of devices. The versatility of rare earth
metals establishes their technological, environmental, economic, and political
importance. Although the elements are generally similar in their geochemical
properties, certain characteristics, as well as their individual concentrations,
are by no means equal to each other.
While this chapter has debunked myths in regard to the rarity of rare earth
metals, it has also described the origins and creation story of rare earth
metals. Processes of supernova nucleosynthesis and nuclear fission shed light
as to how these elements were created and have been embedded within the
interior of our planet. Moreover, this chapter has touched upon topics of great
importance concerning the future of rare earth metal use and productions.
Mining processes for rare earth metals are not safe for the environment and
are not sustainable. With the hope of becoming more environmentally-friendly
and safe, continuous research is necessary to push the boundaries of the
unknown and collectively work towards sustainable methods of rare earth
metal extraction and overall use in society.
The following chapter will focus on the individuals behind the discovery of
rare earth metals, and will shed light on how their research and knowledge
translated into scientific achievements that allow for us to use rare earth
metals today.
24
WHO DISCOVERED THE
RARE EARTH METALS?
Written By Si Cong (Sam) Zhang
Introduction
Many people know that some of the elements in the periodic table are named
after places, people, astronomical objects, or simply the minerals in which they
are commonly found. While many minerals are named after large countries
known for their scientific prowess, many countries don’t appear on the table
at all. So one would expect the United States to top the charts in terms of the
number of elements named after it with berkelium, californium, tennessine
and americium. But, in fact, the champion is Sweden with holmium named
after Stockholm and 4 other rare earth elements named after a sleepy little
village on a small island a 40 minute drive away from downtown Stockholm.
How the village of Ytterby came to be the place with the most elements named
after it is a story that begins long before the invention of the periodic table by
Dmitri Mendeleev or even before the first list of modern chemical elements
were written down by Antoine Lavoisier. This chapter will tell the story of the
discovery of rare-earth metals, and it begins in the village of Ytterby.
History
Knowing that the elements are named after Ytterby, it’s a short leap to guess
that the elements named after the villages are yttrium, ytterbium, terbium,
and erbium; each an interesting attempt by chemists at naming different
elements after the same village.
27
RaRe eaRth Metals: an IntRoductIon
The village of Ytterby is famous for its long history of quartz and feldspar
mines, once supplying the local iron and porcelain industry. In 1787, a Swedish
army artillery officer named Carl Axel Arrhenius visited Ytterby (note that this
Arrhenius is unrelated to Svante Arrhenius, the Nobel laureate in chemistry).
It just so happens that Arrhenius studied the properties of gunpowder in the
royal mint and was an amateur chemist and geologist. During this visit, he
found an especially dense black mineral along with the expected quartz and
feldspar in the rock layers (Voncken, 2015).
A sample of this dense black mineral with attached feldspar was eventually
sent to the Finnish chemist, mineralogist, and physicist Johan Gadolin in the
Royal Academy of Turku (then the University of Abo) in 1792. Through a series
of reactions with heat and other known chemicals, Gadolin was able to deduce
that 38% of the mineral was “of an unknown earth” along with some silica,
iron oxide, aluminum oxide and beryllium oxide which he misidentified as
aluminum oxide (Pyykkö & Orama, 1996). While he was never able to isolate
the unknown elements found within this sample, he was the first to conduct
extensive experimentation and discover that the sample he had contained
substances with chemical properties different from any other that had ever
been discovered (Marshall & Marshall, 2008). Therefore, he is today most
often credited with the discovery of the first rare earth metals.
A colleague of Gadolin, Anders Gustaf Ekeberg was able to obtain a larger
sample of the unknown black mineral without feldspar. He was able to confirm
the discovery of Gadolin and improve upon the original results. Because of
the lack of feldspar in his sample, Ekeberg’s result contained less silica and
aluminum oxide, and his sample contained 47.5% of the unknown earth. He
proposed the name “yttria” for the new earth and “yttersten” (swedish for
ytterbite) for the mineral in 1797 (Pyykkö & Orama, 1996). While the credit
for the discovery of rare earth metals would go to Gadolin, Ekeberg would
leave his name in history by discovering tantalum, which was also from this
same mine in Ytterby. As a side note, because the pair were so focused on the
yttria, they didn’t realize that their “aluminum oxide” actually contained a
large amount of beryllium oxide, and beryllium would instead be discovered
28
Si Cong (Sam) Zhang
one year later in France by Vauquelin (Weeks, 1956/2010).
Soon after, cerium would also be discovered by a pair of Swedes, Jöns Jacob
Berzelius and Wilhelm Hisinger. The more famous of the two, Baron Jöns
Jacob Berzelius is today considered the father of Swedish chemistry and a
founder of modern chemistry. The pair collected samples of what is now
known as cerite from the ore field Bastnäs and were able to derive ceria or
cerium oxide from the sample in the winter of 1803. Berzelius would go on to
discover selenium, and his students would also discover lithium, lanthanum,
and vanadium in his laboratory. While the Swedish pair is now credited with
the discovery, the German chemist Martin Heinrich Klaproth, known for the
discovery of uranium and zirconium, also discovered cerium independently
around the same time as the Swedes (Weeks, 1956/2010). Klaproth would also
rename ytterbite to gadolinite in honour of Gadolin, which became the name
more commonly used today (Klaproth, 1802).
By 1803, yttrium and cerium were identified as yttria and ceria respectively.
However, what the discoverers did not know was that these samples did not
contain one singular element but a mixture of many elements. As stated in
the first chapter, while rare earth elements are not particularly rare, they are
extremely difficult to separate from one another. Because of this property,
even though the samples of ceria and yttria together contained all the rare
earth elements, it was impossible for the elements to be further separated
until more than three decades later
Carl G. Mosander was the first person to be able to separate rare earth metals
from each other. He was educated as a pharmacist and physician, becoming a
close personal friend and assistant to Berzelius during his stay at Karolinska
Institute (a Swedish Medical University) (Weeks, 1956/2010). Following in the
footsteps of his teacher, he was able to further purify the samples of ceria and
yttria. In 1825, he isolated metallic cerium. Although the sample was impure,
he became the first person to isolate a rare earth metal in metallic form, by
reacting cerium sulphide with chlorine and potassium (Cerium, n.d.). Using
the same method Friedrich Wöhler, a fellow pupil and friend of Mosander,
29
RaRe eaRth Metals: an IntRoductIon
was able to isolate metallic yttrium in 1828 (Wöhler, 1828).
In 1839 Mosander heated some of what was thought to be cerium nitrate and
added dilute nitric acid to it. He noticed that some of the “cerium nitrate”
dissolved in the solution, something which is not a property of cerium nitrate.
He was able to separate the dissolved substance and named this new “earth”
lanthana after the Greek word “lanthano”, which means hidden”. The discovery of this unknown earth was initially hidden from Berzelius. It was only
when Axel Erdman, another student of Berzelius at the Karolinka Institute
discovered lanthana in a mineral later named mosanderite,did Mosander
reveal that he had already discovered lanthana (Weeks, 1956/2010).
Mosander would continue his fanatical purification of the sample of ceria for
the next few years, with very little communication of his work to the wider
chemical world or even his close friends Berzelius and Wöhler. Most of what
we know of these years comes from the letters between Berzelius and Wöhler,
in which they jokingly complained about Mosander’s lack of interest in sharing
his work. But Mosander was eventually successful, when in 1841 he was able
to separate what he believed to be a new element: didymium. It was named
after the Greek word for twins “didymus” because Mosander thought of it as
“an inseparable twin brother of lanthanum”. However, unlike cerium, yttrium,
or lanthanum, didymium does not appear on the modern periodic table (but
it does appear as Di with atomic number 138 in Mendeleev’s original periodic
table). This is because, unknown to Mosander, much like the previous supposed
pure elements and despite his best efforts at separation, didymium is still a
mixture of rare earth elements. Despite his failure in this regard, Mosander
was still able to generate many breakthroughs in the discovery of rare earth
metals. He found that the ceria sample contained an insoluble portion, and
soluble portions of lanthana and didymia.(Weeks, 1956/2010).
After having examined ceria, Mosander moved on to purifying yttria with
similar techniques. In 1843, he showed that yttria with the ceria, lanthana
and didymia removed contained at least three more earths. The properties
and names of these newly isolated “earths” are: a colourless oxide, for which
30
Si Cong (Sam) Zhang
he kept the name yttria, a yellow earth which he named erbia, and a rose
coloured earth which he named terbia (Weeks, 1956/2010). Following the death
of Berzelius in 1848 and Mosander in 1858, the study of rare earth elements
was drastically hindered and new discoveries would not be made until two
decades later.
While the names of the elements would remain the same, when Nils Johan
Berlin attempted to replicate the results in 1860, he was only able to produce
yttrium and the rose-coloured substance, which he mistakenly identified as
erbia. Repeating the same experiment in 1862, Marc Delafontaine was able to
produce the yellow substance but at this point the rose substance was already
known as erbia, so he named the yellow substance terbia, resulting in the
current configuration of names for both elements (Holden, n.d.).
In 1878, the Swiss chemist Jean Charles Galissard de Marignac would expand
the list of rare earth elements once more by discovering that erbia (the rose
colored substance) consists of two parts, red erbia and colourless ytterbia.
Following the pattern established by other researchers, L. F. Nilson would
then go on to isolate scandia from ytterbia. In addition to being a new rare
earth element, the discovery of scandium was very significant in the field
of chemistry as a whole, for it is the eke-boron element that Mendeleev had
predicted to exist using his periodic table, filling the gap at atomic number
68 in his original periodic table (Weeks, 1956/2010).
Several other alleged rare earth element discoveries were also made in 1878 and
the years shortly after, many were cases of mistaken identity, but some were
also genuine new rare earth elements. The American chemist J. Lawrence Smith
was able to isolate an element from samarskite which he named mosandrum in
honour of Mosander. But Delafontaine reported that mosandrum did not exist
and was actually terbia. Much later, in 1886, Paul-Émile Lecoq de Boisbaudran
proved mosandrum was a mixture of terbium and holmium. Delafontaine
working with samarskite was able to isolate a supposed element which he
named philippium after Philippe Plantamour. Unfortunately, the sample
of philippium was destroyed in the great fire of Chicago, but in retrospect
31
RaRe eaRth Metals: an IntRoductIon
Si Cong (Sam) Zhang
it was thought to be holmium. In addition to philippium, Delafontaine was
able to identify another element, named decipium, which is now thought to
have been misidentified samarium (The Discovery and Naming of the Rare
Earths—Elementymology & Elements Multidict, n.d.).
Freiherr von Welsbach (Freiherr is a nobility similar to Baron, Freiherr von
Welsbach can roughly be translated to Baron of Welsbach. Auer is his family
name, and Carl is the first name.) (Weeks, 1956/2010).
After the removal of ytterbia and scandia, the leftover erbia was further
studied by the Swedish chemist Per Teodor Cleve. He noted that the atomic
weight of erbium after the removal was not constant. With experimentation, he was able to purify erbia into 3 components: erbia, holmia and thulia.
As stated at the beginning of the chapter, holmium is named after Cleve’s
hometown, Stockholm. Similarly, thulia is derived from Thule, a historic
name for Scandinavia. Holmia’s absorption bands are the same as the philippium previously noted by Delafontaine, therefore they were likely the same
substance (Weeks, 1956/2010).
Returning to the twin element didymia, as far back as 1853, there had been
proposals by Marignac that didymia was not an element but a mix of many
elements. This idea was verified by Delafontaine and Lecoq de Boisbaudran’s
spectroscopic analysis which showed varying spectrums depending on the
source. So in 1879, Lecoq reacted didymium with ammonium hydroxide and
noticed that one part precipitated earlier than the rest. He was able to isolate
this precipitate and find the spectrum of this new substance was different
from that of the rest of didymia. Using this information he deduced that this
was a new element and named it samaria after the mineral samarskite from
which he got his sample of didymia (Weeks, 1956/2010).
Even after the removal of samarium, it was still thought that didymium was
a mixture of more than one element. In 1882, the Czech chemist Bohuslav
Brauner was able to identify two groups of absorption bands within didymium, one in the blue region and another in the yellow region. This discovery
provided additional evidence that the didymium with all other elements
removed was still a mixture of two elements very close in properties. However,
despite efforts from multiple chemists, it would take until 1885 for didymium to finally be separated by the Austrian inventor and chemist Carl Auer,
32
Auer was a favourite student of the great German chemist Robert Bunsen
(inventor of the bunsen burner), and was greatly interested in inorganic
chemistry and rare earth minerals in particular. Under the supervision of
Bunsen, who had extensive knowledge regarding didymium, Auer began his
investigation. His relationship with Bunsen would become extremely useful
when he was finally able to separate didymia using repeated fractionation.
Bunsen was able to quickly recognize Auer’s achievement and supported his
findings in a skeptical scientific establishment. Auer named his two new
elements neodymia (new didymia), and praseodymia (green didymia). Outside
of his work in chemistry, Auer is well-known today for his engineering work,
notably improvements made to gas lamps (Weeks, 1956/2010).
In 1886, Lecoq identified an additional element from his sample of didymium,
but following analysis, it was found that this element was identical to an
element separated from samarskite by Marignac in 1880. Lecoq named this
element gadolinium after the gadolinite in which this element can be found.
In the same year, Lecoq was also able to separate holmium into two different
elements, holmia and dysprosia via fractional precipitation. Because the two
elements are so similar in properties, it took more than 30 attempts to isolate
dysprosia from holmia. Because of the effort he had to endure, Lecoq named
the element after the Greek for hard-to-get “dysprositos” (What Is Dysprosium?
• Earth.Com, n.d.; Weeks, 1956/2010). In addition to discovering many rare
earth metals, Lecoq also discovered gallium, naming it after the Latin name
for France: “Gallia” (Weeks, 1956/2010).
The next discovery was also made by another french chemist, Eugène-Anatole Demarçay. A legendary figure in the field of spectroscopy at the time,
Demarçay was often called upon for the identification of new elements. Lecoq
noticed a faint line in the spectrum of samarium in 1892. After studying the
samarium samples and gadolinium samples, Demarçay proposed that there
33
RaRe eaRth Metals: an IntRoductIon
was another element in between the two in 1896 (Marshall & Marshall, 2003).
In 1901, he conducted a series of fractionations of samarium which yielded
a new element that he named europium. Unfortunately, he died soon after
his discovery in 1904 and was unable to conduct more thorough studies of
europium. In addition to his discovery of europium, he frequently used his
spectroscopy expertise to help Marie and Pierre Curie in their study of radioactive elements and took part in many of their discoveries (Weeks, 1956/2010).
The last of the discoveries were made independently by the French chemist
Georges Urbain as well as Auer at around the same time in 1907. Urbain was able
to separate ytterbia into two elements by repeated fractional crystallization. He
named the components neoytterbia and lutecia. However, neoytterbia would
later be changed back to ytterbia and lutecia to lutetia. Lutetia is named after
the Roman settlement which became modern-day Paris (Weeks, 1956/2010).
At last, over a period of more than one century, every rare earth metal has been
discovered from the original ceria and yttria. The ability for rare earth metals
to blend into each other seamlessly played an integral role in the discovery of
these elements, as the elements were able to be isolated gradually based on
how close they are in properties to each other. Now that we know the history
behind the discovery of these rare earth metals, in the next chapter, we will
find out the important role these metals play in our everyday life.
34
WHAT IS THE ROLE OF RARE
EARTH METALS IN THE WORLD?
Written By Anusha Mappanasingam
Introduction
Rare earth metals are a significant component of modern life. In chapter 1, we
were presented with the 17 different types of rare earth metals. In chapters 2
and 3, we discussed the origins of the rare earth metals and the people who
discovered them. From what we know so far into this book, we have come to
understand how relevant rare earth metals are in our lives. Rare earth metals
make up a crucial component of the periodic table of elements: they include
atomic numbers 57-71, making up Group IIIA (Henderson, 1984). They also
play an important role as components of electronics. When considering this,
it can be surprising to see that many people are not familiar with rare earth
metals. Take yourself back to your high school days: you probably came across
the periodic table of elements in your science classes. In these classes, many of
us are only taught the first 20 elements, from hydrogen to calcium. This can
give off the impression that the rest of the elements are insignificant; many
of us will continue the rest of our lives without ever truly understanding
how significant these rare earth metals are. This chapter will aim to enforce
this understanding by presenting the various roles that rare earth metals
can have in our world. This will be done by considering their role in geology,
geochemistry, and space. While these will be the focuses of this chapter, we
will take some time to consider some roles that rare earth metals can have
in other areas. Even though some of these are prominently impacted by rare
37
RaRe eaRth Metals: an IntRoductIon
earth metals, we will not focus on them in this chapter.
Role in Geology and Geochemistry
To comprehend the role that rare earth metals have in geology and geochemistry, it is first important to understand geology and geochemistry themselves.
Geology is an area of study that tries to understand the earth and its processes;
this can include the study of the structure and materials that make up the
earth, as well as the organisms that inhabit the planet (What is Geology?—
What Does a Geologist Do?—Geology.Com, n.d.). The term ‘geochemistry’ is
referred to as the science of the processes involved in the creation of chemical
compounds and isotopes in different parts of the earth or other celestial
bodies (Definition of GEOCHEMISTRY, n.d.). It is apparent that the subjects of
geology and geochemistry are closely related and that the study of rare earth
metals has a significant contribution to each. In this section, we will consider
this contribution by breaking down the role of rare earth metals in geology
and geochemistry into subsections. This section will cover rare earth metals
and their role in rocks, and radioisotopes and geochronology.
Rocks
It is more difficult to determine the elemental composition of the earth’s crust
than it is to determine that of the sun’s atmosphere (Frey, 1984). Despite this,
we expect there to be an average concentration of around 150 to 220 parts per
million of rare earth metals in the earth’s crust (The Geology of Rare Earth
Elements, n.d.). Most of these rare earth metals are found in very minute quantities inside various types of rock such as igneous, alkaline and carbonatite.
(The Geology of Rare Earth Elements, n.d.). While their presence in various
rocks is crucial in our attempt to understand the role that rare earth metals
have in our world, it is their participation in the formation of many rocks that
requires the utmost attention as this role is vital to many geological cycles.
We will begin by looking at the role of rare earth metals in the upper mantle of
the earth. To do this, we will first consider how the composition of the earth’s
mantle is typically determined. There are various indirect approaches: some
of them include studying liquids obtained from the partial melting of the
38
Anusha Mappanasingam
mantle, while others involve interpreting geophysical data (Frey, 1984). One
thing that is common with these indirect methods is that they all come with
problems that can make their use detrimental to their initial purpose (Frey,
1984). However, there is a single direct approach that can be used instead
of the indirect methods to determine the composition of the upper mantle:
studying obtained samples of the mantle rock with analytic processes (Frey,
1984). It is processes like the direct approach that have allowed geologists to
determine that rare earth metals make up a component of the mantle (Frey,
1984). Researchers have found that the abundance of rare earth metals in
upper mantle rocks have a heterogeneous nature; the variation in elements
ref lects the upper mantle’s heterogeneous nature (Frey, 1984). There is a larger
variation amongst light rare earth elements (LREE) than amongst heavy rare
earth elements (HREE) (Frey, 1984). The details of this abundance are not
relevant to this chapter—this is brief ly discussed in chapter 6. Rather, it is
the implications of its presence in the mantle that are of primary concern.
Rare earth metals can help with understanding upper mantle processes
(McDonough & Frey, 2018). There are two ways in which rare earth metals
in upper mantle rocks appear to be involved in mantle processes: acting
as “a recorder of mantle processes…” and by determining and defining the
heterogeneous nature of the upper mantle (McDonough & Frey, 2018). The
first of these applications mentioned can include a variety of ways in which
rare earth metals serve as records of the upper mantle process (McDonough
& Frey, 2018). Some of these include using rare earth metals to understand
and document partial melting processes, the range of melting that occurs,
and mantle enrichment (McDonough & Frey, 2018). The second application
mentioned can not only provide a direct outlook into the heterogeneous nature
of the elemental composition of the upper mantle, but it can also provide
insight into the heterogeneity of the mantle by helping geologists determine
how various components are distributed within the mantle (McDonough &
Frey, 2018). One example of this is the identification of LREE enrichment
occurring in both the ocean and continental mantle (Frey, 1984). While these
implications mentioned are appearing to be the general ways in which rare
earth metals play a role in the upper mantle of the earth, it is important to
highlight that their implications on the upper mantle are not restricted to
39
RaRe eaRth Metals: an IntRoductIon
Anusha Mappanasingam
these applications. Although in-depth discussions of these are outside the
scope of this chapter, it is enough to know that they exist.
into this role any further, we need to first understand the specifics that allow
rare earth metals to be an asset to geochronology: it is the radioisotopes of
rare earth metals that contribute primarily to our efforts to pursue geochronology (Patchett, 2018).
Rare earth metals are often components of other, larger rock formations. . We
see this with metamorphic rocks (Grauch, 2018). At least 70% of the earth’s crust
is made up of metamorphic rocks (Grauch, 2018). Although it has been found
that these rocks do contain a portion of rare earth metals in them, minimal
research has been done to determine the exact abundance (Grauch, 2018).
Studying the rare earth metals in metamorphic rocks can allow geologists
to become more familiar with their composition, which can help them have a
deeper understanding of the composition of the earth. But rare earth metals
have been proven useful to the study of metamorphic rocks by other means as
well. Studying the rare earth metals’ content in these rocks helps geologists to
determine the origin of meta-igneous rocks, which are transformed igneous
rocks (Grauch, 2018; Definition of METAIGNEOUS, n.d.). Additionally, rare
earth metals have physical and chemical properties that make them ideal for
the study of geochemistry, specifically that of sedimentary rocks(McLennan,
2018). Not only are rare earth metals a component of sedimentary rocks, they
seem to play a role in the sedimentation process itself (McLennan, 2018). While
details regarding the elements’ role in the sedimentary process appear to be
inconsistent and confusing, some details are obvious and will thus be brief ly
discussed (McLennan, 2018). We primarily see this in weathering processes—
processes that cause the breaking down of the earth by physical and chemical
means (McLennan, 2018; Definition of WEATHERING, n.d.). While how the
rare earth metals are distributed differently as a result of weather processes
is barely understood, it is apparent to many geologists that further research
in this area is crucial. Understanding rare earth metals’ chemistry during
weathering processes can help further our knowledge on weathering since
the chemistry of these elements can have effects on sedimentary rare earth
metal patterns. (McLennan, 2018).
Radioisotopes and Geochronology
These metals also have a significant role in geochronology, or the dating of
rocks and minerals (Hawkesworth & Van Calsteren, 1984). Before we delve
40
To begin, let us clarify what is meant by the term ‘radioisotope’—radioisotope,
also known as a radioactive isotope, is a term for isotopes with an unstable
nucleus that spontaneously decompose to form other elements and emit
radiation and other particles in the process (Definition of Radioactive Isotope
| Dictionary.Com, n.d.). Most rare earth elements have radioisotopes with
long lives, making some of them useful for geochemical studies, including
geochronology (Patchett, 2018). Specifically, it is La-138 to Ce-138, Sm-147
to Nd-143, and Lu-176 to Hf-176 decay schemes that could have significant
implications to geochronology and other geological studies (Patchett, 2018).
While their decay schemes are not the primary focus of this section, we will
brief ly discuss them and their ambiguities to gain a better understanding
of the impact that they can have on geological studies. Let us begin with the
decay scheme of La-138 to Ce-138: La-138 undergoes beta-decay—a type of
radioactive decay—to become Ce-138 (Patchett, 2018). Many problems arise
when using La-138 to Ce-138 in studies (Patchett, 2018). One of these problems
is the low abundance and the slow decay nature of La-138—this means that
when geologists are basing studies on this form of decay, they must rely on
small changes in the abundance of Ce-138 to detect beta decay (Patchett, 2018).
However, the latter proves to be unreliable too since this isotope only makes up
0.25% of Ce (Patchett, 2018). This means that geologists must undergo various
procedures to ensure that the correct isotope is being measured—this would
also mean that they might need to amplify the small changes in Ce-138 to detect
them (Patchett, 2018). Sm-147 to Nd-143 decay scheme involves a different type
of decay process known as alpha decay (Patchett, 2018). Unlike the previous
decay scheme discussed, this scheme appears to have fewer hurdles: given
that there is sufficient chemical separation from other rare earth metals, the
composition of the different isotopes of Nd is easy to measure (Patchett, 2018).
The last decay scheme of Lu-176 to Hf-176 decays similar to La-138 (Patchett,
2018). While Lu is relatively easy to measure in a thermal ionization mass
41
RaRe eaRth Metals: an IntRoductIon
Anusha Mappanasingam
spectrometer—a process in which will be brief ly described in chapter 7—Hf
can be difficult to measure (Patchett, 2018).
recognized that this decay scheme also allows for the chronology of entities in
space; this scheme is actually more effective for chronology in space than on
earth (Patchett, 2018). The Sm-Nd decay method was first used for lunar and
meteorite chronology and has since been actively used in lunar chronology
(Patchett, 2018). While these rare earth metals contribute to lunar chronology
in multiple ways, their most significant initiative has been in determining the
age of lunar crust formation (Patchett, 2018). This method also contributes
significantly to determining the ages of meteorites (Patchett, 2018).
The radioactive decay schemes of Sm-Nd have made significant contributions to
geological dating (Patchett, 2018). This method was originally used in geological
dating involving entities in space, which will be discussed in the next section
(Patchett, 2018). These rare earth metals used in space chronology led to it
appearing relatively useful to the geochronology of our earth—although the
contribution is incomparable to its role in dating entities in space (Patchett,
2018). An example where the radioactive decay of Sm to Nd was found to be
successful in geochronology was the dating of metamorphic rocks (Patchett,
2018). While the role of Sm-Nd in geological dating appears to be relatively
significant in both space and earth, the radioactive decay schemes of La-Ce and
Lu-Hf have provided minimal contributions to geochronology so far (Patchett,
2018). Overall, it is important to recognize that the roles of these radioactive
isotopes of rare earth elements in geochronology are more complex than
what has simply been discussed so far. However, the details are irrelevant to
understanding the overall idea that rare earth metals are significant to our
understanding of geology and geochemistry.
Role in Space
When thinking of rare earth metals, many typically associate them with
our earth. While this is expected, it is essential to highlight that rare earth
metals have an equally important role in space (Patchett, 2018). Similar to
what has been discussed regarding the role of rare earth metals in geology
and geochemistry, studying rare earth metals in space allows for a more
thorough understanding of the processes involved in forming the entities
containing these rare earth metals (Hawkesworth & Van Calsteren, 1984).
Specifically, the abundance of rare earth metals provides cosmologists with
a better insight into the formation of rocks in space, including meteorites
(Hawkesworth & Van Calsteren, 1984).
As discussed in the previous section, the radioisotope decay scheme of Sm-147
to Nd-143 assists in geochronology (Patchett, 2018). However, it must be
42
Rare earth metals are invaluable to our understanding of space and the
universe.This is true not only because of the role that rare earth metals have in
meteorite dating and understanding cosmological processes, but because they
simply exist in space in sufficient quantities. Their abundance in space has led
individuals to explore the potential of extracting these rare earth metals from
space via mining, the latter being a process that we will brief ly touch upon
in this chapter and will be discussed more thoroughly in chapter 9 (Cockell
et al., 2020). A new study presenting results from experiments conducted
on the International Space Station show that microbes could potentially be
used for mining in space (Cockell et al., 2020). Specifically, the bacterium
Sphingomonas desiccabilis was found to be able to extract 14 rare earth metals in
space with the same degree of effectiveness as on earth (Cockell et al., 2020).
Overall, initiatives like this one are inspired by the importance of rare earth
metals that are uncovered through the study of the roles they have in space.
Other Roles
While the focus of this chapter has been on the role of rare earth metals in
geology, geochemistry, and space, rare earth metals have uses in other fields
too. One example is the roles that rare earth metals have in technology (REE—
Rare Earth Elements—Metals, Minerals, Mining, Uses, n.d.). Rare earth metals
are used in many personal electronic devices such as cell phones, magnets,
and batteries (REE—Rare Earth Elements—Metals, Minerals, Mining, Uses,
n.d.). To fully grasp the necessity of rare earth metals in technology, refer to
the next chapter, where more details on their important role in electronics
can be found. Additionally, we must recognize that because of how important
43
RaRe eaRth Metals: an IntRoductIon
technology is in daily life, mining these rare earth metals becomes a necessity
(REE—Rare Earth Elements—Metals, Minerals, Mining, Uses, n.d.). While
we will refrain from going into the details of the mining process, as it is
not relevant to this chapter, it is essential to understand the environmental
implications of our increasing mining activities, as they can have disastrous
consequences (REE—Rare Earth Elements—Metals, Minerals, Mining, Uses,
n.d.). More details on the environmental implications can be found in chapter 9.
Conclusion
In conclusion, this chapter discussed the role of rare earth metals in the world.
Firstly, we looked at the role of rare earth metals in geology and geochemistry.
This was done by considering the role that these metals have in rocks and
radioisotopes and geochronology. Then we looked at the role of rare earth
metals in space. Lastly, we brief ly discussed the other roles that rare earth
metals might have in other fields.
The many ways in which rare earth metals are associated with our world are
obvious. In the next chapter, we will discuss the importance of rare earth metals.
44
WHY ARE RARE EARTH
METALS SO IMPORTANT?
Written By Rishi Mohan
Introduction
The rare earth metals are a group of 17 elements consisting of scandium,
yttrium and the 15 elements contained in the lanthanide series. They are
found in the earth’s crust in trace amounts and must undergo a robust process
in order to be separated and gathered in large quantities. However, due to
the important role of rare earth metals, the benefits of mining them greatly
outweigh the negatives. In this chapter, the importance of rare earth metals
will be assessed. This will be done by first determining how rare earth metals
impact the daily lives of a typical individual living in the western hemisphere.
Next, the role of rare earth metals for the purpose of innovation will be
examined. Finally, the importance of rare earth metals in established power
dynamics will be addressed.
The Importance of Rare Earth Metals in Our Daily Lives
The 17 metallic elements that comprise the rare earth metals, are integral
components to many of the electronic devices you use on a daily basis (King,
2021). The reason this is the case is because rare earth metals possess unique
properties that make them desirable for a wide range of potential applications
(Kirkpatrick, 2019). Rare earth metals have an intrinsic resistance to high
levels of heat, strong magnetic properties and act as an excellent conductor
of electricity (Kirkpatrick, 2019). Electronic devices like the smartphone in
47
RaRe eaRth Metals: an IntRoductIon
Rishi Mohan
your pocket, the television in your living room or the laptop you take to work
with you would not function without the incorporation of rare earth metals
in their design (Logsdon & Lanthanum, 2013).
is important to mention that it would still be possible to create devices capable
of communication, browsing the internet and scrolling through social media
without the use of rare earth metals (Butters, 2016). However, these devices
would not be nearly as efficient or light as the current iterations that contain
rare earth metals (Butters, 2016). In fact, you would be hard-pressed to refer
to those devices as smartphones because, without the addition of rare earth
metals in their design, they would display information in black & white and
be the size of a classroom (Butters, 2016). This is because electronic devices,
like a smartphone, require a constant magnetic f lux (Gutf leisch et al., 2011).
Smartphones rely on the transmission of electromagnetic pulses from the
battery to power the device (Gutf leisch et al., 2011). Alloys containing the
rare earth metal dysprosium, are used to create these magnets because they
are more resistant to the effect of demagnetization at higher temperatures
when compared to non-dysprosium containing alloys (Gutf leisch et al., 2011).
The addition of the rare earth metal neodymium, in alloys contained within
smart devices facilitated the transition to smaller and more efficient iterations of devices like computers, smartphones and televisions (Gutf leisch et
al., 2011). A reduction in the size of these devices was possible because of the
aforementioned unique properties of rare earth metals. In addition to this,
rare earth metals are required to produce full colour displays, as previously
stated (Leskelä & Niinistö, 1992). Phosphors, a synthetic f luorescent or phosphorescent substance containing rare earth metals, can be used to generate
red, blue and green light (Leskelä & Niinistö, 1992). From these primary colours,
in combinations of varying amounts, the other colours that constitute the
remainder of a full colour display can be generated (Leskelä & Niinistö, 1992).
The Integral Role of Rare Earth Metals in Our Daily Electronic Devices
Since their inception, the amount of individuals using a smartphone has
increased drastically over time (Brown, McGregor & McMillan, 2014). Smartphones provide users with various technical applications such as audio
communication, Bluetooth connectivity and barcode scanning among others
(Brown, McGregor & McMillian, 2014). Not only do smartphones provide us
with more technical capabilities, they also augment our lives in various ways
(Brown, McGregor & McMillian, 2014). To investigate their role in our lives,
let’s start by analyzing the ways in which the average iPhone user utilizes
their smartphone on a daily basis.
In Canada, approximately 56% of smartphone users own an iPhone (Bennett,
2018). In addition to this, first quarter sales in 2018 revealed that the amount
of iPhone users in the country have increased by 4% (Bennett, 2018). Every
one of these iPhones contain eight rare earth metals in their design (Rohrig,
2015). The integration of these rare earth metals in the design of an iPhone is
what gives it the ability to produce the red, blue and green colours that create
a colour display (Rohrig, 2015). In addition to this, rare earth metals are also
utilized in an iPhone’s circuitry and audio output (Rohrig, 2015). Furthermore, without the addition of rare earth metals, specifically neodymium
and dysprosium, these smartphones would not be able to vibrate (Rohrig,
2015). Thus, the iPhone is an excellent example of how rare earth metals play
an important role in our daily lives.
A group of researchers from Stockholm University conducted a study to determine how iPhone users utilize their smart device. They found that, on average,
participants allotted approximately 80% of their smart device time towards
communication, internet browsing and social media use (Brown, McGregor
& McMillian, 2014). In the paragraph above, various iPhone functions that are
enabled through the inclusion of rare earth metals were mentioned. However, it
48
Although the importance of rare earth metals in everyday electronics was
analyzed through the example of a smartphone, the subsequent findings
can be generalized to all other everyday electronic devices. Those electronic
devices utilize rare earth metals in a similar way. Take a moment to consider
how the implementation of rare earth metals into these everyday electronic
devices has impacted modern-day culture. We now live in an era where access
to information is at an all-time high thanks to integration of rare earth metals
in smart devices. For instance, without the popularization of smart devices,
49
RaRe eaRth Metals: an IntRoductIon
Rishi Mohan
we would not have apps that wake us up on time, guide us on our route to
work, ensure we are sticking with our diet and a plethora of other aspects.
Even in the realm of electronic entertainment, consider how different the
internet would be without the convenience and full colour capabilities that
rare earth metals provide. It is arguable that the markets for industries
like video streaming services or social media would be completely different
without the technological benefits that rare earth metals provide. Based on
the information provided above, it would be no stretch of the imagination
to say that rare earth metals play an integral role in our day to day activities.
imaging began in 1895 with the invention of X-ray imaging (Bradley, 2008).
X-ray images can be used to determine bone fractures and cancerous tumours
(Bradley, 2008). However, X-ray images still had some shortcomings. X-rays
provided 2D images of the scanned area and the diagnostic results were relegated to dense tissue, like bones (Bradley, 2008). This meant that if there were
irregularities with the patient’s soft tissues or arteries, they would go largely
undetected (Bradley, 2008). Fortunately, innovations like CT, or computerized tomography, and PET, or positron emission tomography, imaging were
invented to circumvent the issue (Bradley, 2008).
The Importance of Rare Earth Metals Regarding Innovation
Rare earth metals are an integral component in the functionality of these
medical imaging and diagnostic tools (Ascenzi et al., 2020). Due to the unique
properties of rare earth metals, they are the optimal material to serve as
scintillators in CT and PET scanning (Ascenzi et al., 2020). Scintillators are
materials that are able to convert high energy radiation or particles into light
that can be detected by an electronic sensor (Ascenzi et al., 2020). Scintillators
are responsible for converting the emitted radiation so that it is readable by
a 3D imaging software (Ascenzi et al., 2020). In this way, rare earth metals
play an invaluable role in the detection of medical diseases.
From the previous section you saw how important rare earth metals are to our
daily lives. However, beyond that, the implementation of rare earth metals
is vital to innovation. Humans seek to improve upon the current iterations
of systems and tools. Sticking with our previous example, think about how
much the design and capabilities of the current iPhone has improved upon
that of the original iPhone in such a short period of time. There are two
primary drivers for innovation. The first is innovation through inspiration.
This would be akin to the addition of a feature to an iPhone that was not
present on previous iterations but was in other smartphones on the market.
The second driver of innovation is necessity. This would be equivalent to the
material of the latest iPhone iteration being so brittle that it bends when it is
put in your pocket. In this scenario, the design team would need to improve
upon the structural composition in order to make the iPhone a feasible option
for consumers. Ultimately, innovation is borne out of a need to eliminate an
obstacle or problem. In the upcoming section, we will examine two sectors
related to the survival of humankind to illustrate how rare earth metals are
used as vehicles for innovation.
The Integral Role of Rare Earth Metals in Medical Innovations
Those in the field of medicine aim to discover, understand and treat diseases
that arise in patients. Due to this fact, innovative approaches are often
required. One department of medicine that has seen a large amount of innovation recently is the realm of diagnostics. The subdiscipline of medical
50
The Integral Role of Rare Earth Metals in Emission-Free Innovations
Scientists have long been sounding the alarm regarding fossil fuels and climate
change.(Nolt, 2011). This problem is another that can be solved by innovation
due to necessity. One potential solution to reduce the output of emissions is
to transition from fossil fuel powered vehicles to ones that are powered exclusively by electric batteries. Doing this would significantly reduce the amount
of harmful emissions produced by human actions. Like in previous cases,
rare earth metals play an important role in getting humankind to that point.
The application of rare earth metals in the automotive industry is not a novel
idea. Currently, rare earth metals are utilized in the motors of most vehicles,
both fossil fuel and electric ones, because they allow the motor to be permanently magnetized (Gutf leisch et al., 2011). Nickel metal-hydride batteries,
the kind of batteries used in hybrid electric vehicles, require a significant
51
RaRe eaRth Metals: an IntRoductIon
Rishi Mohan
amount of rare earth metals in their design (Sakai, Matsuoka & Iwakura, 1995).
Nickel metal-hydride batteries confer many environmental and functional
benefits. They are rechargeable and have a higher energy capacity than their
acid counterpart (Sakai, Matsuoka & Iwakura, 1995). In addition to this, nickel
metal-hydride batteries last longer than the batteries that do not incorporate
rare earth metals (Sakai, Matsuoka & Iwakura, 1995). Nickel metal-hydride
batteries can be reused up to 1000 times, whereas non-rechargeable batteries
can only be used once (Sakai, Matsuoka & Iwakura, 1995). Finally, most components from nickel metal-hydride batteries can be recycled and the by-products
are less toxic than other batteries (Sakai, Matsuoka & Iwakura, 1995).
China has done. China dominates the rare earth metal industry, having the
rest of the world rely on them to supply this commodity (Mancheri, Sundaresan & Chandrashekar, 2013). In the past, China has also leveraged their
economic prowess in the realm of politics, as evident with their decision to
not supply Japan with rare earth metals after the two nations had a political
disagreement (Mancheri, Sundaresan & Chandrashekar, 2013).
Another way to reduce the amount of harmful emissions is to switch to greener
sources of energy. Whilst hydropower and bioenergy are the front runners in
that department, solar and wind energy are expected to grow rapidly within
the coming years (Pavel et al., 2017). In 2016, wind energy accounted for a little
over 10% of the total quantity of clean energy produced in Europe (Pavel et al.,
2017). The International Energy Agency anticipates that the quantity of energy
sourced from wind turbines will increase until 2050 (Pavel et al., 2017). Wind
turbines require the inclusion of rare earth metals, specifically: neodymium,
praseodymium, dysprosium and terbium for their unique magnetic properties
(Pavel et al., 2017). These rare earth metals play an integral role in facilitating
the function of the permanent magnet synchronous generator contained in
wind turbines (Pavel et al., 2017). Therefore, rare earth metals are undoubtedly
important in helping humankind transition to a zero emission society. Despite
their importance to the green energy industry, it is important to note that
the process of extracting these rare earth metals can have severe detrimental
environmental effects. To learn more about how the extraction of rare earth
metals impacts the planet, refer to Chapter 9.
The Role of Rare Earth Metals in Creating Power Dynamics
The previous subsections have made it apparent that rare earth metals are
important because they impact our lives in various ways. Therefore, it stands
to reason that the nation that produces the largest supply of rare earth metals
would distinguish themselves as a global economic power. This is exactly what
52
Even though China is the biggest supplier of rare earth metals, the United
States is the nation responsible for most of the breakthroughs associated with
those elements (Mancheri, Sundaresan & Chandrashekar, 2013). This topic is
discussed in greater detail within Chapter 10. In earlier sections some of the
technological uses of rare earth metals popularized by the United States were
referenced. However, one that has yet to be mentioned is the importance of
rare earth metals in regards to national defence. The rare earth metal yttrium
for example is used in militaristic equipment like radar systems (Jha, 2014).
The use of rare earth metals for battlefield equipment confers many benefits
such as being lightweight and reliable (Jha, 2014). Regardless of whether you
weigh power based on economic or militaristic might, it is hard to argue
against the fact that rare earth metals play an important role in establishing
a power dynamic.
Conclusion
In summary, this chapter examined the importance of rare earth metals.
The unique abilities of rare earth metals, such as their intrinsic resistance to
high levels of heat, strong magnetic properties and their electric conductivity
make them desirable components for a wide array of potential applications.
Some of these applications include the electronic devices we use on a daily
basis, like smartphones, laptops, computers and televisions. Without the
integration of rare earth metals in these devices, they would be robbed of
the convenience, efficiency and full colour display that popularized them in
the first place. Rare earth metals are a vehicle of innovation. Medical diagnostics and clean energy are two sectors that have experienced a large level
of innovations thanks to rare earth metals. Finally, the sway that rare earth
metals have in determining power dynamics was also explored. This was
53
RaRe eaRth Metals: an IntRoductIon
done so by analyzing how China has used its position as the world’s primary
supplier of rare earth metals to distinguish itself as an economic powerhouse.
On the other hand, the United States utilizes rare earth metals in militaristic
applications to strengthen their prowess on the battlefield. The next chapter
examines the current status of rare earth metals.
54
WHAT IS THE STATUS OF RARE
EARTH METALS TODAY?
Written By Joonsoo Sean Lyeo
Introduction
Due to their importance in the manufacturing of high technology products,
rare earth metals are highly sought after by businesses and governments
alike (Campbell, 2014). In recent years, this demand for rare earth metals has
grown exponentially(Campbell, 2014). As a result of this growing demand, as
well as the incorporation of rare earth metals into new and emerging technologies, the general public has grown concerned with the dwindling supply
of rare earth metals (Schlinkert & van den Boogaart, 2015). This chapter will
be dedicated to discussing the current status of rare earth metals in terms
of their abundance, their strategic value, and their future role in the global
supply chain.
Abundance of Rare Earth Metals
Despite their name, the so-called ‘rare’ earth metals are relatively abundant
in the Earth’s upper continental crust (Campbell, 2014). In fact, rare earth
metals are just as common, if not more common, than most other types of
metals used commercially (Campbell, 2014). For instance, the rare earth metal
yttrium is about as abundant as lithium; a key ingredient in rechargeable
batteries (Zepf, 2016). As another example, the rare earth metals neodymium
and lanthanum are about as abundant as copper; a metal so common that it
was used to make tools in early human civilizations dating back eight thousand
57
RaRe eaRth Metals: an IntRoductIon
years (Zepf, 2016). Even dysprosium, a rare earth metal that was only isolated
in the 1950s, is twice as abundant as gold and eight times as abundant as
platinum; both of which are commonly used to make false teeth (Zepf, 2016).
If rare earth metals are so abundant, then what’s with their name? Is it some
kind of misnomer? Well, although rare earth metals are indeed fairly abundant
throughout the Earth’s crust, these numbers don’t ref lect their distribution
or their ease of access (Zepf, 2016). For instance, while some metals, such as
gold or copper, can be found in naturally occurring concentrated deposits—
such as veins, nuggets, and rock matrices—rare earth metals are unlikely to
accumulate in any significant concentration (Campbell, 2014). As a result, it
is extraordinarily rare to find naturally occurring rare earth metals in their
pure, uncombined form—never mind on a scale that could be considered
commercially accessible (Campbell, 2014). As a result, in most commercial
settings, rare earth metals are typically collected as a byproduct of more
plentiful and easily accessible resources (Campbell, 2014). For instance, rare
earth metals are often collected as a byproduct of the mining of mineral-rich
sands—known as heavy sands—clay, iron ore, and tin (Campbell, 2014).
That being said, even in these settings, rare earth metals only ever make
up a small portion of the overall material collected through these processes
(Campbell, 2014).
With this in mind, let’s revisit our assessment from the beginning of this
subsection. While yttrium is indeed about as abundant as lithium, the 7,000
tonnes of yttrium mined each year is dwarfed by the 36,000 tonnes of lithium mined in the same period (Zepf, 2016). Similarly, the 19,800 tonnes of
neodymium and 23,300 tonnes of lanthanum mined each year almost seem
negligible when compared to the 1.55 million tonnes of copper mined each
month (Zepf, 2016). Finally, in terms of annual production, the 100 tonnes of
dysprosium produced worldwide lags behind the 142 tonnes of gold produced
in Ghana alone—keep in mind that Ghana is only the seventh-largest producer
of gold ore (Holmes, 2019).
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Joonsoo Sean Lyeo
History of Global Rare Earth Metal Production
Historical trends in the global production of rare earth metals can be divided
into three distinct time periods: (1) the Monazite Phase, (2) the Mountain Pass
Phase, and (3) the Chinese Phase (Naumov, 2008). Each of these periods will
be discussed below.
The first of these periods, the Monazite Phase, began in the late 19th century
(Naumov, 2008). It was characterized by the extraction of rare earth metals
from heavy sand deposits, especially those containing high concentrations of
monazite minerals; hence the name (Naumov, 2008). While monazite sands
often had a relatively low rare earth metal content, these deposits could be
processed using relatively simple methods, thus allowing for significant rare
earth metal production at the expense of time and manpower (Naumov,
2008). The United States was one of the first countries to engage in large-scale
monazite sand mining with the intent of yielding commercial quantities of
rare earth metals, beginning with an 1893 pilot project based in North Carolina
(Naumov, 2008). It wasn’t long before other countries followed suit and, by
the 1950s, the global demand for rare earth metals was largely supplied by
mining operations in Australia, Brazil, China, India, Malaysia, South Africa,
Sri Lanka, and Thailand (Naumov, 2008). Note that despite being one of the
first countries to take an interest in the mining of rare earth metals, the
United States wouldn’t become a major force on the rare earth metals market
for quite some time (Naumov, 2008).
The second of these periods, the Mountain Pass Phase, began in the 1960s
(Naumov, 2008). As the global demand for rare earth metals increased, spurred
by the invention and subsequent mass production of coloured television
sets, the United States was graced with the discovery of a large deposit of
carbonatite rock—containing a number of rare earth metal compounds—in
Mountain Pass, California (Zepf, 2016). For a twenty-year-long period, lasting
from 1965 to 1985, the Mountain Pass Mine was single-handedly responsible
for supplying the majority of the global demand for rare earth metals (Castor,
2008). Throughout this period, the Mountain Pass Mine dwarfed production
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RaRe eaRth Metals: an IntRoductIon
Joonsoo Sean Lyeo
at the second-largest mining operation of rare earth metals—the Bayan Obo
Mining District in China—which only produced relatively meagre quantities
of rare earth metals as a byproduct of its iron mining industry (Campbell,
2014). This status quo would soon come to an end.
damages has allowed its rare earth metal mining operations to thrive in the
absence of prohibitive environmental restrictions, a factor that contributed
to the closure of the Mountain Pass Mine (Campbell, 2014). In other words,
the lack of severe environmental restrictions allows China’s metal mining
operations to focus on maximizing their productivity without needing to
reallocate their attention or resources to meeting environmental regulations
(Campbell, 2014). He argues that because Chinese rare earth metal mining
companies don’t face the same pressure to adopt environmental regulations,
they are well poised to compete with and undermine the costs of rare earth
metal production elsewhere (Campbell, 2014). It should be acknowledged
that this disregard of environmental regulations often comes at a cost to
those who live near rare earth metal mining operations, a factor which will
be discussed in greater detail in Chapter 9.
The third and final period, known as the Chinese Phase, began sometime in the
mid-1980s (Naumov, 2008). It began with the discovery of a giant bastnäsite
rock deposit in the Bayan Obo Mining District which, to this day, remains the
world’s largest deposit of commercially accessible rare earth metals (Naumov,
2008). This single deposit is estimated to contain approximately 36 trillion
tonnes of rare earth metal oxides, a figure accounting for a colossal 70% of
the world’s known rare earth metal reserves (Drew, Qingrun & Weijun, 1990).
This momentous discovery coincided with a period of reduced productivity
at the Mountain Pass Mine, which in turn could be attributed to a series
of environmental restrictions that had been enforced following a scandal
regarding the mine’s improper waste disposal procedures (Naumov, 2008).
This disruption to the status quo allowed the Bayan Obo Mining District to
wrestle away the Mountain Pass Mine’s former monopoly over the rare earth
metal market, usurping this title for itself (Naumov, 2008). The Mountain
Pass Mine was ultimately unable to recover from this setback and, after a
period of steady decline, eventually ceased operations in 2002, leaving the
Bayan Obo Mining District with an iron grip on the rare earth metal market
(Castor, 2008).
With regards to the latter point, Dr. Campbell also stresses the importance
of the Bayan Obo Mining District which—as mentioned prior—extracts rare
earth metals as a byproduct of its iron mining operations (Campbell, 2014).
Due to the high domestic demand for steel, China is able to subsidize much
of its activity at the Bayan Obo Mining District through the sale of iron ore,
allowing them to continually operate the site regardless of f luctuations in the
market price of rare earth metals (Campbell, 2014). As a result, the Bayan Obo
Mining District can afford to stockpile rare earth metals to be processed at a
later time, for instance when the market price of rare earth metals has risen,
allowing them to fully take advantage of market trends (Campbell, 2014).
Current Global Rare Earth Metal Production
So where does this leave us? To this day, China continues to maintain its
monopoly over the rare earth metal market, with the country currently
supplying about 85% of the world’s demand for rare earth metals (Paulick
& Machacek, 2017). China has continued to tighten its hold over the market,
owing much of its success to a combination of environmental passiveness
and market economics (Campbell, 2014).
With regards to the former, Dr. Gary Campbell—from the Michigan Tech
College of Business—notes that China’s willingness to accept environmental
60
That being said, while China’s current grip on the rare earth metal market is
undeniable, several ongoing trends suggest that this monopoly may be challenged in the near future (Paulick & Machacek, 2017). For instance, as a result
of the 2008-2013 Rare Earths Trade Dispute—in which China limited its rare
earth metal export quotas, causing a sharp hike in the market prices of rare
earth metals—some governments have begun to question whether China’s
monopoly over the rare earth metal market constitutes a strategic concern
(Paulick & Machacek, 2017). The issue was further compounded in September
of 2010, when Japan accused China of deliberately restricting its export of rare
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RaRe eaRth Metals: an IntRoductIon
Joonsoo Sean Lyeo
earth metals to harm the Japanese economy (Campbell, 2014). Japan claimed
that this was a calculated ploy by the Chinese government, implemented as
retaliation for the Minjinyu 5179 Incident; a political confrontation over the
disputed waters around the Senkaku Islands (Campbell, 2014).
4000-5000 meters below the surface, contained high concentrations of rare
earth metals such as gadolinium, cerium, europium, and yttrium (Kato et al.,
2011). With great excitement, the research team announced that they were
able to extract almost all of the rare earth metals—with the sole exception
of cerium—from the seaf loor mud samples using a relatively simple metal
leaching technique (Kato et al., 2011). Using this technique, the team was able
to harvest most of the desired rare earth metals in less than 3 hours, pointing
to the potential commercial viability of future deep-sea mining endeavours
(Kato et al., 2011). Finally, in an optimistic conclusion, the research team
estimated that an area covering one square kilometre of the Pacific seaf loor
could, at least in theory, supply up to one-fifth of the annual global demand
for rare earth metals (Kato et al., 2011).
These incidents have caused some governments to reconsider their willingness
to accept China’s inf luence on the global supply of rare earth metals, prompting
a wave of investments in rare earth metal mining outside of China (Paulick
& Machacek, 2017). The aforementioned Mountain Pass Mine, for instance,
was reopened in 2012 with the intent of reviving America’s once-dormant
rare earth metal industry (Zepf, 2016). As of 2020, the Mountain Pass Mine
is expected to supply 15% of the global demand for rare earth metals and has
already received praise for reducing the United States’ reliance on rare earth
metal imports (Gambogi, 2021). Aside from the revitalization of the Mountain Pass Mine, investments have also been directed towards emerging rare
earth metal production facilities in Australia, Canada, Greenland, and Kenya
(Paulick & Machacek, 2017). This has culminated in a substantial increase in
the volume of rare earth metal production outside of China, with the total
annual production increasing from 40 megatonnes to 98 megatonnes (Paulick
& Machacek, 2017).
Future Global Rare Earth Metal Production
Thus far, this chapter has primarily focused on the extraction of rare earth
metals from terrestrial sources—i.e. where rare earth metals can be dug up
from the ground. While this may seem like the most intuitive way of accessing
rare earth metals, recent innovations have allowed us to gauge new possibilities, considering opportunities that are not yet available to us, but may
become viable within the next few decades. This subsection will be dedicated
to discussing some of the emerging technologies allowing for unconventional
methods of rare earth metal production.
Deep-Sea Mining
In 2011, a research team from the University of Tokyo determined that mud
samples retrieved from various points along the Pacific seaf loor, more than
62
In 2018, this statement was supplemented by the findings of a second research
team from the University of Tokyo (Takaya et al., 2018). The second team
surveyed the seaf loor surrounding Minamitorishima Island and determined
that the sediments in the delineated area, covering an area of about 105 square
kilometres, contained enough yttrium to meet the global demand for the next
62 years (Takaya et al., 2018). This team also ran a series of experiments using
a hydrocyclone separator—a device that uses centrifugal force to extract
desired components from a solid-liquid slurry—to test the commercial viability
of extracting rare earth metals from sediment samples (Takaya et al., 2018).
The results were promising, prompting the researchers to consider how this
device could be implemented on a larger scale (Takaya et al., 2018). In their
final report, the team expressed their optimism regarding the potential implementation of deep-sea mining projects in the near future (Takaya et al., 2018).
Asteroid Mining
In light of the growing discussion around the commercialization of space
travel, some think tanks have suggested that the mining of near-Earth asteroids may serve as a potential solution to terrestrial resource shortages (Hein,
Matheson & Fries, 2020). Due to the immense costs associated with the
theoretical mining and transportation of near-Earth asteroids, nevermind
the costs associated with the heat shielding of cargo during atmospheric
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RaRe eaRth Metals: an IntRoductIon
Joonsoo Sean Lyeo
reentry, these think tanks recognize that very few resources would, at least
from a financial standpoint, warrant asteroid mining (Hein, Matheson &
Fries, 2020). In order to be considered commercially viable, the resource in
question would need a high market-value-to-mass ratio—a criterion which
rare earth metals happen to fit perfectly (Hein, Matheson & Fries, 2020). Of
course, with little opportunity to study the practical aspects of mining asteroids for rare earth metals, much of the current research has been limited to
discussing the theoretical economic viability, technological limitations, and
legal considerations of such endeavours (Hein, Matheson & Fries, 2020).
Several companies have also taken an interest in the recycling of rare earth
metals from the alloys found in rechargeable batteries (Ferron & Henry, 2015).
For instance, the Honda Motor Company has set aside facilities dedicated
to the recycling of decommissioned nickel metal hydride batteries (Ferron
& Henry, 2015). As of 2015, Honda’s facilities were reportedly capable of
processing 400 tonnes of material each year, allowing the company to recycle
80% of rare earth metals—equivalent to 24 tonnes of rare earth metals each
a year—through this process (Ferron & Henry, 2015). Similarly, Umicore—a
Belgian materials technology company—has developed a plant capable of
processing up to 7,000 of batteries each year (Ferron & Henry, 2015). The
recycled rare earth metals yielded from this process are typically sold to other
Belgian companies, such as Solvay and Rhodia, to be repurposed as part of
their line of products (Ferron & Henry, 2015).
Recycling
In recent years, a growing number of efforts have been dedicated to assessing the feasibility of recycling rare earth metals from end-of-life consumer
products (Ferron & Henry, 2015).
Conclusion
For instance, some recent innovations have allowed for the recycling of the rare
earth metals used to manufacture permanent magnets; the type of magnets
present in hard drives, audio equipment, and electric motors (Ferron & Henry,
2015). Generally speaking, the recycling of rare earth metals from permanent
magnets takes one of two forms: (1) the recycling of rare earth metals as blended
metals, or (2) the recycling of rare earth metals as separated oxides (Ferron &
Henry, 2015). Both processes have their own advantages and disadvantages.
For instance, the first process—the recycling of rare earth metals as blended
metals—offers the advantage of being less energy-intensive, but comes with
the disadvantage of yielding an inseparable blend of metals and impurities
(Ferron & Henry, 2015). As a result, the rare earth metals recycled through this
process are generally only able to be repurposed for the same function as the
original product (Ferron & Henry, 2015). Conversely, the second process—the
recycling of rare earth metals as separated oxides—is comparatively more
energy-intensive and chemically-complicated (Ferron & Henry, 2015). However,
because this process is analogous to the current practices of the recycling
industry, it presents the advantage of being easier to integrate into existing
facilities on a meaningful scale (Ferron & Henry, 2015).
64
This chapter was dedicated to discussing the status of rare earth metals in
several different contexts. First, this chapter discussed the abundance of rare
earth metals in relation to other commercially used metals, highlighting the
distinction between geological abundance and commercially relevant abundance.
Next, this chapter sought to provide a brief overview of the historical trends
in the global production of rare earth metals, so as to provide context for the
current market for rare earth metals. Finally, this chapter concluded with an
analysis of how recent and emerging technological innovations may allow for
the production of rare earth metals through previously untapped means. For
more information on the science behind the study of rare earth metals, please
refer to the next chapter.
65
WHAT SCIENCE IS INVOLVED
IN STUDYING THE RARE
EARTH METALS?
Written By Anittha Mappanasingam
Introduction
Rare earth metals play a hidden, yet vital part in our daily life. Whether we
are able to recognize it or not, rare earth metals are the foundation for many
of the things that we deem important today, such as electronics, space, and
the economy. Because of its essential applications, the production of it is inevitable, hence the processes must be carefully monitored to ensure that they
are occurring in the most efficient and effective way possible. The production
of rare-earth metals involves three steps—mining of the rare earth metals,
separation of the valuable ore from other waste compounds, and purification
of the ore to separate out the metal (Science of Rare Earth Elements, 2019).
Although these steps are fairly similar when processing most other metals,
with rare earth metals, it typically involves an additional stage—separating
rare earth metals from each other (Science of Rare Earth Elements, 2019).
This last step is often incredibly difficult and costly, creating the need to use
complex separation techniques, some of which will be discussed as we get
further into the chapter (Science of Rare Earth Elements, 2019).
In order to understand if the processes being used to produce rare earth
metals are ideal, we must first understand the science behind these various
techniques. By understanding the science, individuals will be able to figure
out new ways to improve the current processes, or create new ones, to produce
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RaRe eaRth Metals: an IntRoductIon
Anittha Mappanasingam
rare earth metals. As a result, this chapter will go into the science behind
various processes used in the separation of rare earth metal production,
and the science behind the analytical methods used to produce rare earth
metals. Specifically, the science behind separation techniques, such as solvent
extraction, chromatographic separation and adsorption, will be reviewed.
When discussing the science behind analytic techniques, we will specifically
discuss mass spectrometry and emission spectrometry.
product, mixed product, or individual rare earth salt (Xie et al., 2014). The
latter purpose, producing individual rare earth salts, is extremely difficult
because the elements that make up these metals usually all display similar
chemical properties (Science of Rare Earth Elements, 2019). These rare earth
metals contain an outermost electron shell that is filled in a similar way which
gives them similar reactivity, hence making it dif ficult to separate them
individually (Science of Rare Earth Elements, 2019). Because of this, solvent
extraction is typically used in order to obtain higher concentrations of specific
metals, as a previously used technique, ion-exchange chromatography, was
only able to produce smaller amounts of higher concentrations (Science of
Rare Earth Elements, 2019; Xie et al., 2014).
Science in Separation
Separating rare earth metals is the most important part of the production
of rare earth metals. The scientific basis underlying the separation process
varies between techniques. The impact of these processes on the environment
is undeniable as we will learn more in chapter 9. So, researchers and producers
are always trying to find new ways to create more efficient and affordable
methods to extract rare earth metals. In this section of the chapter, we will be
discussing three key techniques that are normally used to separate rare earth
metals—solvent extraction, chromatographic separations, and adsorption.
Solvent Extraction
Solvent extraction is the most common method used to separate rare earth
metals (Science of Rare Earth Elements, 2019). Not only is it used in the separation process, but it is also used while processing other substances in the
nuclear and food industry (Anderson, n.d.) Brief ly, solvent extraction involves
separating compounds based on their solubility (Schaller, 2013). Each solvent
dissolves a different compound, allowing scientists the choice of which metal
to extract (Schaller, 2013).
The solvent extraction process is fairly similar when applied to rare earth
metals. The specificities of the solvent extraction method used may vary
based on a couple of factors, such as the composition of rare earth metals
used and the purpose of the extraction (Xie et al., 2014). The process begins
by separating the rare earth metals from the contaminated water, called
leachate (Xie et al., 2014). The remainder of the process then depends on
the purpose of the extraction—whether it is to be sold as an intermediate
68
After the solvent-solute mixture has been extracted from the raw ore, this
method typically involves the addition of an extractant to an organic solvent, in
which the extractant will dissolve (Cheisson & Schelter, 2019). An extractant is
a compound used to extract a substance, in this case, rare earth metals, from a
liquid, and can take the form of either an acidic extractant, neutral extractant,
or basic extractant, depending on the solvent that the rare earth metal is in
(Xie et al., 2014). So when the extractant is mixed with the organic solvent and
is in contact with the solvent containing rare earth metal components, the rare
earth metals are able to separate into the organic solvent (Cheisson & Schelter,
2019). However, this occurs at extremely slow rates (Science of Rare Earth
Elements, 2019). Eric Schelter, the director of the Center for the Sustainable
Separations of Metals, explains it as initially starting with a 50/50 concentration of the rare earth metal in both solvents, and then after one extraction,
ending up with a 60/40 concentration (Science of Rare Earth Elements, 2019).
Although his description reinforces that this process is extremely inefficient,
this is only the case when viewing it from a single extraction, and over the
years, chemical engineers have been able to develop solvent extraction into
an effective process (Science of Rare Earth Elements, 2019).
Chromatographic Separations
Separation via chromatography was one of the first separation techniques to
be used to extract and purify large amounts of rare earth metals (Cheisson &
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RaRe eaRth Metals: an IntRoductIon
Anittha Mappanasingam
Schelter, 2019). There are many different types of chromatography techniques
that are used to separate rare earth metals, however, the most common one
is liquid chromatography (Chen et al., 2017). Essentially, chromatography is
a separation technique involving the isolation of individual components of a
mixture based on the speed at which these substances move in the solution
(Chromatography, 2013). The rate at which the components move through this
solution is dependent on a variety of factors, such as molecular weight and
affinity (Coskun, 2016). There are three key components of this process: the
stationary phase, the mobile phase, and the separated molecules (Coskun,
2016). The stationary phase is a medium that is always either solid, or liquid
fixed on a solid frame, while the mobile phase is the liquid solvent in which the
sample is injected (Coskun, 2016). Once the sample is injected, it attaches to
the stationary phase with varying strength, depending on the sample (Coskun,
2016). As the solvent passes through, it separates the compounds based on a
given factor, such as affinity (Coskun, 2016). The component with the most
affinity will be the last to reach the end of the column (Coskun, 2016). There
are many different types of chromatography techniques, and this process
varies between each technique and factor used (Coskun, 2016).
separation method that is used, prior to the discovery of solvent extraction
(Chen et al., 2017). In general, chromatography is typically advantageous in
its speed—it is able to separate multiple metals with very few repeats, making
it extremely cost-ef fective (Chen et al., 2017; Rare Earth Elements(REE):
Industrial Technology, Smelting Process-Metalpedia, n.d.).
Along with the previously explained method, liquid chromatography that is
often used for the separation of rare earth metals, another type of chromatography that is used to separate rare earth metals is extraction chromatography
(Monroy-Guzman et al., 2020). Unlike liquid chromatography, extraction chromatography is used to isolate metals from aqueous solutions (Monroy-Guzman
et al., 2020). In this type of chromatography, the stationary phase is typically
an organic liquid based on a solid support, and an aqueous solvent containing
the rare earth metals is used as the mobile phase (Monroy-Guzman et al.,
2020). The solvent is then evaporated, leaving the extractant within the pores
of the solid support material (Monroy-Guzman et al., 2020).
Another chromatography technique that is used is gas chromatography,
however, it is only used when scientists need to isolate volatile compounds
(Chen et al., 2017). In particular, when individuals are isolating rare earth metal
ions, ion exchange chromatography is the ideal type of liquid chromatography
70
Adsorption
Adsorption is another fairly common technique used for the separation and
purification of rare earth metals. In recent years, adsorption has become a
favourite for rare earth metal producers; reasons for which will be discussed
later in this chapter (Hu & Xu, 2020). In summary, adsorption is the process
in which molecules are held to the surface of another solid phase (Nix, 2015).
The stability of the molecules that hold onto the solid surface is weak due
to the unbalanced forces created by the residual surface energy of the solid
phase (Hu & Xu, 2020). Only select molecules are able to hold onto the surface,
and of those that do, the bond they have to the surface is relatively weak (Hu
& Xu, 2020). The remaining steps can be split into two types of adsorptive
processes: physical adsorption and chemical adsorption (Hu & Xu, 2020).
Physical adsorption occurs due to the interactions of intermolecular forces,
and because these forces are typically weak, the adsorbed substance can be
easily separated (Hu & Xu, 2020). Chemical adsorption involves the formation
and destruction of chemical bonds (Hu & Xu, 2020). In comparison to physical adsorption, chemical adsorption is a bit more difficult to complete and
is still relatively weak (Hu & Xu, 2020). Both absorptions occur together and
still produce weak attachments of the adsorbed substance (Hu & Xu, 2020).
In the context of rare earth metals, adsorption occurs in this manner. The
adsorbent substances are often selectively chosen so that particular rare
earth ions collect on the adsorbent surface and form a thin, molecular film
(Asadollahzadeh et al., 2020). Scientists are able to obtain specific results
by altering easily controlled parameters of the adsorption process (Asadollahzadeh et al., 2020). Some of the various adsorbent substances that are
typically used include granular hybrids, carbonized polydopamine nano
carbon shells, modified red clay, zeolite, and silica (Anastopoulos et al., 2016;
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RaRe eaRth Metals: an IntRoductIon
Asadollahzadeh et al., 2020).
Unlike some of the other methods discussed, adsorption can extract rare
earth metals from low concentration solutions, making this technique an ideal
option for cleaning industrial wastewater prior to its release into groundwater
(Asadollahzadeh et al., 2020). This process has become a favourite among
industrial producers in order to remove metals from wastewater (Hu & Xu,
2020). In addition to its role in the environment, adsorption is also widely
appreciated because of its simplicity, high effectiveness and low-cost (Anastopoulos et al., 2016).
Science in Analysis
Another important aspect of producing rare earth metals is being able to
identify them. Not only are analytical techniques critical for producing rare
earth metals and research, but also to clean out wastewater. In order to
separate the elements, individuals must be able to determine the metals that
they are working with. In this part of the chapter, we will be discussing the
two categories under which the majority of the analytical techniques that are
used today fall—mass spectrometry and emission spectrometry.
Mass Spectrometry
Prior to the development of mass spectrometry, analysts experienced a very
difficult time determining the presence of rare earth metals in geological
samples (Balaram, 2019). It wasn’t until the development of particular types
of mass spectrometry that individuals were able to easily find the presence
of rare earth metals in various samples. Mass spectrometry is an analytical
technique used to determine the presence of compounds, and study their structure and reactivity based on their mass-to-charge ratios (Zagorevskii, 2003).
Scientists are able to identify various molecular properties such as ionization
energy, bond dissociation energy, and proton affinity (Zagorevskii, 2003).
Mass spectrometry is able to identify the molecule by measuring its mass.
However, this can only be done once the molecule is converted into a gas-phase
ion (Zagorevskii, 2003). Ionization is a critical step for molecules that are
going to undergo mass spectrometry (Zagorevskii, 2003). Essentially, the
72
Anittha Mappanasingam
sample undergoes vaporization so that when it goes through the ionization
chamber, it can give off electrons (Zagorevskii, 2003). It is able to do this
due to the heat being emitted from that chamber (Zagorevskii, 2003). These
electrons will collide with electrons from the sample molecule, resulting in
positively charged ions (Zagorevskii, 2003). These positively charged ions are
now def lected by a magnetic beam within the spectrometer (Zagorevskii,
2003). The amount of def lection that occurs is dependent on the mass and
charge of the ions (Zagorevskii, 2003). Heavier molecules will be def lected
less than the lighter ones, and the ions with a charge greater than +1 will be
def lected more as well (Zagorevskii, 2003).
In terms of analyzing rare earth metals, there are more specific types of mass
spectrometers that are used. Some of these different mass spectrometers
include, but are not limited to:
• inductively coupled plasma mass spectrometry (ICP-MS),
• glow discharge mass spectrometry (GD-MS),
• Isotope dilution thermal ionization mass spectrometry (ID-TIMS), and
• spark source mass spectrometry (Balaram, 2019).
Out of these options, ICP-MS is the most commonly used technique for
analyzing trace concentrations of rare earth elements in aqueous samples
(Wysocka, 2021). ICP-MS is a type of mass spectrometry that allows for the
detection of extremely low concentrations of a specified element (Bulska &
Wagner, 2016). It differs from mass spectrometry by its usage of inductively
coupled plasma for ionization of the molecule (Bulska & Wagner, 2016). The
inductively coupled plasma provides energy for ionization by electric currents
produced by electromagnetic induction (Bulska & Wagner, 2016). It converts
the atoms of the metal to ions (Balaram, 2019). With the high temperatures
accompanied by the plasma source in this specific type of mass spectrometry, almost all rare earth elements can be ionized (Balaram, 2019). After this
ionization step has occurred, the mass spectrometry happens as previously
discussed, and these ions are categorized based on their mass (Bulska &
Wagner, 2016).
Many analysts prefer the use of ICP-MS for analyzing rare earth metals due
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RaRe eaRth Metals: an IntRoductIon
Anittha Mappanasingam
to its multi-elemental capability, very low detection limits, short analysis
time and simple sample preparation (Wysocka, 2021). It encompasses various
different types, such as ICP time-of-f light MS (ICP-TOF-MS) and high resolution-ICP-MS (HR-ICP-MS) (Wysocka, 2021). ICP-MS is sometimes coupled
with other techniques such as chromatographic separation and neutron
activation analysis (Balaram, 2019).
The remaining methods that were only brief ly mentioned in this chapter,
do possess the ability to identify rare earth elements; however because of
their tedious sample preparation and high costs, they are not used as often
as ICP-MS (Wysocka, 2021). Ultimately, its ability to provide fairly accurate
results for incredibly low concentrations has allowed for its consistent use
for many years.
x-ray f luorescence spectrometry,
laser-induced breakdown spectroscopy (LIBS),
inductively coupled plasma optical emission spectrometry (ICP-OES)
and
• microwave plasma atomic emission spectrometry (MP-AES) (Balaram,
2019).
These techniques are quite popular amongst analysts and are often used as
an alternative to mass spectrometry (Balaram, 2019). With x-ray f luorescence
spectrometry, there are specific types in which the method differs. However,
the overall difference between x-ray f luorescence spectrometry and the other
emission spectrometry techniques, is that this method uses x-ray beams to
induce excitation (Balaram, 2019). LIBS uses a laser as its source of energy
for excitation, while ICP-OES uses an external plasma energy source to
cause excitation (Balaram, 2019). Lastly, MP-AES is a fairly new analytical
instrument and is similar to ICP-OES (Balaram, 2019). It involves the use of
nitrogen gas to generate microwave plasma, which allows for the excitation
of the atom (Balaram, 2019). MP-AES, although fairly new, if proven to be
equally effective and precise, is a low-cost alternative to ICP-OES (Balaram,
2019). A significant advantage of LIBS is that it is capable of real-time identification of rare earth metals in a matter of seconds (Balaram, 2019). All of
these methods are extremely effective, however, some of them appear to have
unique advantages over others.
Emission Spectrometry
Emission spectrometry is another analytical technique that is used to identify
the quantity of an element present in a sample. Although this type of spectrometry provides us with similar information about a particular sample,
the methods underlying emission spectrometry differ from those used in
mass spectrometry. With emission spectrometry, atoms are excited from a
higher energy state to a lower energy state, they emit radiation in the form of
photos (Shah et al., 2020). This technique then measures the wavelengths of
these photos to determine the characteristics of the atoms that emitted them
(Shah et al., 2020). Each sample consists of unique wavelength properties,
hence making the element identifiable based on the emitted radiation (Shah
et al., 2020). There are many different types of emission spectrometry and
they differ from one another by their way of inducing excitation. For example, f lame emission spectrometry uses heat to incite excitation, while atomic
emission spectrometry uses light (Shah et al., 2020).
Using emission spectrometry for the analysis of rare earth metals follows
a very similar process, however, this too depends on the type of emission
spectrometry technique being implemented. When looking at the applications
to rare earth metals, there are about four common emission spectrometry
techniques that are used:
74
•
•
•
Conclusion
In this chapter, we discussed the science behind two of the aspects involved in
the production of rare earth metals: separation and analysis. In particular, we
examined the science involved in three major separation techniques: solvent
extraction, chromatographic separation and adsorption. When discussing the science of analytical techniques, we specifically looked at the two
most common analytical techniques used in the identification of rare earth
metals: mass spectrometry and emission spectrometry. Understanding the
science behind the production of rare earth metals is extremely important.
The negative impact that these processes have on our world is not a mystery,
however, the importance of these rare earth metals is also undeniable. Hence,
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RaRe eaRth Metals: an IntRoductIon
individuals need to understand these processes to brainstorm better and
newer technologies, so that we can continue to have access to the rare earth
metals while ensuring that the negative inf luence that it is having on the
world is decreasing.
The following chapter will discuss the questions regarding rare earth metals
that individuals still struggle to answer.
76
WHAT QUESTIONS DO WE
STILL HAVE ABOUT RARE
EARTH METALS?
Written By Ashna Hudani
A
s discussed in previous chapters, we rely on rare earth metals for many
of our daily activities; they are present in everything from the laptops and
cell phones we use to the catalytic converters in our cars. Although they are
commonly found in everyday objects, there are still many unanswered questions about rare earth metals. This chapter focuses on some of these questions.
In particular, as the threat of climate change intensifies every day, both the
availability and accessibility of rare earth metals are important to consider,
given that rare earth metals are important components of renewable energy
technology, and can thus aid in our progress towards greater environmental
sustainability. Furthermore, the mining of rare earth metals has far-reaching
impacts on human and ecological health as well as human rights. In order to
make our strides towards a more climate-friendly future meaningful, it is
important that these benefits are equitable and inclusive for people around the
world. Thus, we must question how and where mining will take place in order
to achieve this goal. The discussion of these concerns in this chapter will only
scratch the surface of these large, but essential, questions about rare earth
metals. However, it is important for readers to continue this conversation,
and collaborate with others to promote and innovate healthy and sustainable
practices in rare earth metal mining and usage.
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Ashna Hudani
Do we have enough rare earth metals to meet clean energy targets?
This is a complex question, the answer to which is unpredictable and depends
on several factors: the discovery of new reserves, the advent of new and innovative renewable technology, changes in the supply chain, geopolitical relations,
and new environmental and trade policies. Although China’s monopoly on the
rare earth metal markets grants them the power to control the supply chain,
there are many concerns with the large-scale mining of rare earth metals in
China that must be taken into account. First, the environmental costs of this
mining have been damaging not only to the landscape, but also to the health
of people living near the mines (Hongqiao, 2016). Research has shown that
producing one tonne of rare earth oxides produces 200 cubic metres of acidic
wastewater (Hongqiao, 2016). This pollution is exacerbated by illegal mining
creating supply in the black market, which may be two to three times the
size of the legitimate market in China (Hongqiao, 2016). In 2014, the Chinese
government declared a “war on pollution,” and established environmental
protection laws and standards for the rare earth metal industry on emissions
and the use of water and energy (Hongqiao, 2016). Increasing costs of mining
and processing of rare earth metals are anticipated (Hongqiao, 2016). Coupled
with the depleting reserves, this creates uncertainty about whether the supply
from China will be sustained in order to meet clean energy targets.
Global climate change has been referred to as the “biggest threat to security
that modern humans have ever faced” (United Nations, 2021). With an alarming
increase of atmospheric greenhouse gas concentrations due to human activity,
we face the imminent collapse of systems on which we rely, including food
production, access to fresh water, habitable ambient temperature, and ocean
food chains (United Nations, 2021). As this threat becomes more pressing,
global leaders are stressing the importance of transitioning to clean energy
(Chen, 2019). In 2015, the Paris Climate Agreement was drafted, which 190
countries signed, committing to reduce their emissions by implementing
renewable energy technologies, and moving away from fossil fuels (Hongqiao, 2016). Commiting to transition to clean energy sources, these countries
increased the demand for materials, including rare earth metals, that make
this technology possible—including solar panels, wind turbines, electric
vehicles, and large-scale batteries (Chen, 2019).
China possesses the largest known reserves of rare earth metals in the world
(Chen & Zheng, 2019). With approximately 23% of the world’s total reserves,
China has satisfied more than 90% of the world’s demand for decades, becoming the largest exporter and consumer of rare earth metals globally (Chen
& Zheng, 2019). Because of their unique physical and chemical properties,
rare earth metals are indispensable and non-substitutable in the emerging
renewable technologies (Chen & Zheng, 2019). Thus, having the world rely on
China for rare earth metal exports is concerning (Chen & Zheng, 2019). This
is, firstly, because they are able to implement stringent exportation policies,
as they did in 2010, resulting in a surge in the price of rare earth metals (Chen
& Zheng, 2019). In addition to this, more than half of all rare earth metals in
China are extracted from the city of Ganzhou, in the southeastern province
of Jiangxi, where reserves are quickly becoming depleted (Hongqiao, 2016).
This brings us to a daunting question: given the current global supply chain
dynamics of rare earth metals, and their irreplaceable role in renewable
technology, will there be enough rare earth metals to meet the clean energy
targets outlined in the Paris Climate Agreement?
80
How do rare earth metals in soil impact ecological and human health?
Although soil is a primary destination for most byproducts containing rare
earth metals, little is known about their effects in this environment, including
their effects on plants, animals, and humans (Ramos et al., 2016). The few
studies that have been conducted suggest that rare earth metals accumulate
in animals over time, particularly in the bones, liver and lungs (Hirano &
Suzuki, 1996; Rim et al., 2013). This has caused cardiac, hepatic, hematological, and renal problems, as well as other effects in the gastrointestinal
tract, bones, central nervous system, and in the pulmonary and cytogenetic
systems (Li et al., 2013; Hirano & Suzuki, 1996; Rim et al., 2013). In spite of
these studies, there is not enough information to determine safe levels of
exposure in humans (Ramos et al., 2016). In addition, it is challenging to
identify pathways in which humans will be directly exposed to salts and oxides
of rare earth metals, although the major exposure routes are understood to
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Ashna Hudani
be ingestion of food, water, and contaminated soil, as well as dermal contact
and inhalation of fumes and particulate materials (Ramos et al., 2016). These
different routes of exposure will have different effects on humans, so they
need to be studied in greater detail (Ramos et al., 2016). In the future, to better
understand the ecological and human health risks associated with rare earth
metals, studies about bioaccessibility, and toxicology need to be conducted
(Ramos et al., 2016). These studies can be used to generate a database, where
estimates of safe doses can be compiled, so that relevant stakeholders have
access to consistent information (Ramos et al., 2016).
prevalent during the mining process, where practices including child labour,
slavery, violation of workers rights, and racial and sexual discrimination
(Martin & Iles, 2020). The use of security forces to protect mining projects
contributes to conf lict and human rights abuses (Martin & Iles, 2020). The
damage to communities well-being and livelihoods continues long after the
mining projects are completed. Water and land contamination from tailings, which destroys local livelihoods, can last for hundreds of years (Martin
& Iles, 2020). Tailings are finely ground residual liquid wastes created by
separating the undesired material from the ores, which can include metals,
f luorine, radionuclides, and processing chemicals (Martin & Iles, 2020).
Although these dangerous byproducts require careful storage and disposal,
they are often carelessly discarded (Martin & Iles, 2020). For example, in a
mining operation in Baotou, China, leakage from tailing ponds has destroyed
farmland and contaminated crops, destroying once-productive livelihoods
(Martin & Iles, 2020). Contaminated water in this region has been linked to
high cancer rates and other health problems, causing affected communities
to migrate (Martin & Iles, 2020). In the span of ten years the population has
reduced from two thousand to three hundred people (Martin & Iles, 2020).
If the contaminated groundwater reaches the Yellow River, up to 150 million
people may be exposed to the same risks (Martin & Iles, 2020).
Is it possible for rare earth metal mining to be safe, sustainable,
and ethical?
Although the health effects of rare earth metals in soils still need to be studied,
there is compelling evidence that mining of rare earth metals is dangerous for
human health, due to the co-extraction of thorium and uranium, which are
radioactive metals (Polo-Gonzalo, 2021). In addition to this, the mining process
itself causes massive environmental damage (Penke, 2021). In order to separate
rare earth metals from other ores, mining companies have adopted a process
of spraying acid over the mining areas, which are often abandoned after they
are polluted (Penke, 2021). Not only does this scar the land for generations, and
cause harm to nearby communities, but it also destroys valuable ecosystems
that are home to diverse species (Penke, 2021). For example, in Madagascar,
the illegal mining sector has been linked to rainforest depletion and destruction of natural lemur habitats (Penke, 2021). Harming the environment, and
indirectly, the people and organisms who depend on that environment, does
not complete the picture of the harm that this multi-billion-dollar industry
does. The mining sector has historically violated, and continues to violate,
people’s basic human rights. This may begin as early as the initial prospecting stage, when mining companies seek to obtain rights for local land and
resources, in order to secure the project (Martin & Iles, 2020). Through this
process, companies may choose to negotiate with government officials, failing
to attain local communities’ permission and ignoring traditional land tenure
systems (Handelsman, 2002). This violation of indigenous land rights often
results in protests and conf licts (Martin & Iles, 2020). Labour abuses are also
82
These pressing issues bring to light an important question: is it possible for
rare earth mining to be safe (to workers, indigenous and local communities,
and the general population), environmentally sustainable, and ethical? Of
course, this question is not easily answered, and requires the conviction and
commitment of many different stakeholders, the most important of whom
are government officials and mining companies. However, there are some
interesting routes that the future of rare earth metal production may take,
which may tackle some of these issues. Firstly, e-waste recycling allows for
rare earth metals to be recovered from electronic products, including phones
and laptops, once they reach the end of their life (Pozo-Gonzalo, 2021). New
methods are being researched and developed to ensure that the process of
recovering earth metals from e-waste is energy-ef ficient, cost-ef fective,
and environmentally friendly (Bhave et al., 2019). Not only can this reduce
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Ashna Hudani
the amount of waste ending up in landfills, but can also reduce the damage
caused by the mining industry—both to humans and the environment.
Another similar undertaking is using electrodeposition to recover rare earth
metals (Pozo-Gonzalo, 2021). Through this process, highly stable and environmentally friendly ionic liquids are used to recover rare earth metals,
like neodymium, without generating any byproducts (Pozo-Gonzalo, 2021).
Similar to e-waste recycling, this process can avoid the need to mine for
rare earth metals, minimizing the generation of toxic waste, and increasing
economic returns from e-waste in the process (Pozo-Gonzalo, 2021). Besides
the advent of such innovative technology to reduce the need for mining, it is
important that companies causing harm to individuals and communities are
held accountable for their violations, and that regulations are put in place to
prevent such harm from recurring.
terrestrial supply of rare earth metals—or even become the dominant source
of them—in the future?
Can ocean floor sediments be a source for rare earth metals?
Previous sections of this chapter have addressed the increasing demand
for rare earth metals, and the decreasing supply, which may slow down the
global transition to decarbonization and the commitment to clean energy.
This has caused governments, researchers and corporations to invest time and
resources into finding an alternative source for rare earth metals in the ocean
(Marranzino, 2020). In the 1970s, researchers first began exploring how the
wealth of minerals on the seaf loor could be extracted and transported to the
surface (Marranzino, 2020). Although interest dwindled shortly thereafter,
fifty years later, the current high demand for natural resources, has led to
a surfacing interest in exploring deep-sea mineral deposits (Marranzino,
2020). Studies show that the concentration of rare earth metals is 10-100 times
higher in deep sea sediments, as compared to seawater (Milinovic et al., 2021).
In addition to ocean-f loor sediments, abundant rare earth metal resources
can be found in polymetallic nodules, cobalt rich Fe-Mn crusts, and seaf loor
massive sulfides—all of which occur between 400 and 6000 metres below sea
level (Marranzino, 2020; Milinovic et al., 2021). Through explorations in the
last decade, abundant rare earth metals resources have been found at several
sites in the Pacific and Indian Ocean (Milinovic et al., 2021). This raises an
important question: can ocean f loor sediments supplement the dwindling
84
In considering the risks of extracting rare earth metals from ocean-f loor
sediments, it is important to consider the potential environmental damage
that can occur. At the present time, the environmental impact of deep-ocean
seabed mineral extraction is little known, and will depend on the deposit
type and extraction tools used (Milinovic et al., 2021). However, there is a lot
of concern about damage that mining will inf lict on already fragile marine
environments (Marranzino, 2020). Removing surface sediments and large
swaths of the sea f loor will impact the organisms living there (Marranzino,
2020). Vehicles extracting rare earth metals will likely generate large sediment
plumes that can travel beyond the mining site, impacting animals elsewhere
(Marranzino, 2020). Pumps transporting minerals to the surface of the ocean
will likely be loud, creating noise that can travel hundreds of kilometres in every
direction, disrupting the communication and behaviour of animals like whales
(Marranzino, 2020). Furthermore, similar to mining operations in terrestrial
ecosystems, the release of tailings can pollute water and damage the health
of many organisms (Marranzino, 2020). This disruption to food chains can
have far reaching consequences not limited to the oceans (Marranzino, 2020).
According to the United Nations Convention on the Law of the Sea, all mineral
deposits found in international waters are considered “common heritage of
mankind” (Marranzino, 2020). Thus, the International Seabed Authority (ISA),
which is composed of 168 member states, is responsible for ensuring that the
marine environment will be protected from any mining activities (Marranzino, 2020). However, we are still very far from understanding exactly what
the effects of such activities may be, making it challenging to develop and
implement regulations that can meaningfully reduce the harmful impacts
(Marranzino, 2020).
Conclusion
The rare earth metal mining industry is currently at a pivotal stage—not only
is it important for the supply to be maintained in order to reach clean energy
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RaRe eaRth Metals: an IntRoductIon
targets that are important for reducing the impacts of climate change, but
the industry must also reform their practices to reduce their harm to local
communities and ecosystems. This has created many questions about ethics
and sustainability, while also prompting research into developing alternative
ways of extracting and recovering rare earth metals, namely through e-waste
recycling, electrodeposition, and even mining deep sea sediments. The future
of mining depends on the ongoing research and development of these methods,
which will inform how and where this extraction or recovery will take place.
86
HOW DOES RARE EARTH
METAL MINING AFFECT THE
ENVIRONMENT?
Written By Pareesa Ali
Introduction
Rare earth metals are vital to the production of many consumer products,
from cell phones and computer hard drives, to electric vehicles. Without the
discovery of rare earth metals, many of these products that we rely on and
use in our daily lives would not exist today. In addition, the previous chapters have discussed the use of rare earth metals, as well as their status in the
modern world. However, despite the contributions these metals have made
in terms of electronics, there is also a downside to the mining and application
of rare earth metals. These processes have significant harmful effects for
our environment and can be dangerous for our surroundings. Thus, in this
chapter, I will discuss the harmful side of rare earth metal mining on the
environment, and on human health. To begin, I will first cover the process of
rare earth metal mining and how it contributes to pollution. Understanding
the harmful side to this process is the first step to working towards a solution
for combatting these dangerous effects, to protect our planet as well as our
own health. Next, I will discuss the impact of this mining on agriculture and
the aquatic environment. Following this, I will uncover the impact of earth
metal mining on animals, as well as on human health. Finally, I will discuss
the potential for remedying these toxic effects, and ways to combat the pollution and detrimental effects on the environment in the future. Overall, earth
metal mining is an important process in our world today; however, its effects
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Pareesa Ali
on the environment can be long-lasting and can have a negative impact on
our environment, as well as our health.
if the contained elements spill out (Ali, 2014). Thus, rare earth metal mining
presents the opportunity for several environmental concerns, from radiation
to air pollution, all of which can be incredibly harmful for the environment
unless they are effectively contained (Ali, 2014).
The Harmful Side of Earth Metal Mining
The amount of identified rare earth metal deposits around the world are close
to a thousand; however, there are only a few operating mines (Haque et al.,
2014). The most prominent mines are currently in China, the United States,
and Australia (Haque et al., 2014). The process of rare earth mining can be
open pit, underground, or leached in-situ (Haque et al., 2014). For an open pit
mine, the process is similar to most typical mining operations, which involve
the following steps: removal of overburden, mining, milling, crushing and
grinding, separation or concentration (Haque et al., 2014). Underground
mining, on the other hand, is used for mining hard rock deposits, while
leached in situ mining involves artificially dissolving minerals using a solution to extract them (Haque et al., 2014). These mining processes require high
amounts of water and energy usage, and produce large amounts of tailings
and wastewater (Haque et al., 2014). Furthermore, the production of consumer
products from rare earth metals leads to the accumulation of post-production
wastes, such as scraps and sludge produced during the shaping and grinding
of materials (Haque et al., 2014).
In addition, rare earth elements sometimes contain radioactive isotopes,
which need to be carefully monitored to keep track of any emissions (Ali,
2014). In particular, the uranium deposits and mining sector require close
monitoring to ensure radiation is not emitted into the outer atmosphere (Ali,
2014). Another process which raises concern for radiation is the production of
another rare earth metal: thorium (Ali, 2014). The decay process for thorium
involves alpha particle emissions, which cannot travel far, but can cause major
damage to the cells if inhaled (Ali, 2014). This decay process is also a major
cause for air pollution, which is detrimental to all living things, as well as to
the environment itself (Ali, 2014). Aside from monitoring radiation levels,
most industrial operations require environmental monitoring of air, water
and soil quality (Ali, 2014). This is because the wastewater treatment plant has
the potential for pipe leakage, which can cause major environmental harm
90
The Impact of Earth Metal Mining on Agriculture
Now that we have discussed the overall harmful effects of earth metal mining
on the environment, let’s move on to the impact of mining specifically on
agriculture. The processing of rare earth metals is known to produce large
amounts of waste and other materials responsible for pollution (Huang et
al., 2016). These pollution-intensive materials include tailings, which are
a mixture of crushed rocks and processing f luids from the mining mills
(Huang et al., 2016). These tailings contain hazardous contaminants from
the rocks and extraction reagents, as a result of the multiple steps involved
in processing the metals (Huang et al., 2016). This mining waste can then
end up in groundwater, rivers, lakes, soil and the air (Huang et al., 2016). For
instance, China, which hosts Bayan Obo, one of the most prominent mining
facilities in the world, is suffering from significant environmental pollution
due to the mining of rare earth metals (Huang et al., 2016). The ponds near
Bayan Obo were all found to contain high levels of chemicals, and due to
evaporation in the lake, the wastewater contained dangerously high levels of
toxins in the environment (Huang et al., 2016). Furthermore, the dams near
Bayon Obo had no cover over the vegetation, which put it at risk for toxins to
enter the surrounding water and soil through pond leaking, f loating dust,
or rain erosion (Huang et al., 2016).
While the concentration levels of these toxins remains low in soil, plants, and
water, they can accumulate over time in these environments due to the low
mobility of these elements, as they cannot travel on their own (Li et al., 2013).
Over the past few years, rare earth metals have been a cause for concern due
to their persistence in the environment, their accumulation in plants and soil,
and their potential for causing chronic toxicity (Li et al., 2013). The presence
of contaminants from rare earth metals can significantly impact the growth
and safety of agricultural produce (Li et al., 2013). Studies have shown that a
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Pareesa Ali
high concentration of these contaminants in soil leads to absorption and accumulation by the plants and vegetables grown in that soil, making it difficult
for the plants to thrive and putting the edible produce at risk (Li et al., 2013).
Therefore, the excess concentration of rare earth metals in agricultural soils
can have significant consequences for the ecosystem, groundwater, agricultural productivity, and animal and human health (Li et al., 2013).
harmful toxins can have significant impacts on the life cycles of aquatic
species (Adeel et al., 2019). Now that we have covered the harmful effects
of rare earth contaminants on animal health, let’s move on to the impact of
these toxicants on human health.
The Impact of Rare Earth Metals on Animals
As discussed above, the presence of rare earth metals in soil can eventually
transfer into the vegetables and other agricultural crops grown in that soil (Li
et al., 2013). These elements can then be harmful for the animals who consume
them (Pagano et al., 2015). However, there is a high level of variability in this
relationship, as rare earth elements are often also used as feed additives for
livestock (Pagano et al., 2015). This is because they have the ability to enhance
feed intake, digestion of nutrients, and milk, egg, and meat production
(Abdelnour et al., 2019). Researchers hypothesize that this is because rare
earth elements have the potential to inhibit bacterial growth, which led
to the enhanced results seen in the livestock (Tariq et al., 2020). However,
low levels of rare earth elements can also stimulate bacterial growth, so the
amount of elements being given to the animals has to be carefully controlled
and monitored (Tariq et al., 2020).
In the natural world, on the other hand, animals who consume these elements
through vegetables and agricultural crops, have suffered harmful effects
(Pagano et al., 2015). Animal toxicity studies have indicated high levels of toxins
in the liver, lungs and blood of animals who consumed these contaminants
(Pagano et al, 2015). In addition, the aquatic environment is also put at risk
when rare earth elements enter and pollute the groundwater and other bodies
of water nearby (Squadrone et al., 2019). This leads to the contamination of
aquatic plants and seaweed, eventually leading to the exposure of marine
animals to the toxic metals (Squadrone et al., 2019). The polluted water and
exposure of aquatic species to these toxins results in effects such as growth
inhibition, tail deformities, delayed embryonic development, reduced hatching
and survival rate, and reproductive toxicity (Adeel et al., 2019). Thus, these
92
The Impact of Rare Earth Metals on Human Health
The impact of rare earth toxicants on the health of agricultural crops, and
aquatic and animal life has a direct and indirect impact on human health due
to the food chain (Adeel et al., 2019). When humans consume foods which
were exposed to these contaminants, the human body accumulates these
toxins through digestion and absorption (Li et al., 2013). These contaminants
can enter the human body through the food chain in a variety of ways (Adeel
et al., 2019). For instance, sources of contaminants can be through seafood,
vegetables, f lower herb tea, wheat, maize and legumes (Adeel et al., 2019). In
addition, toxic pollutants may enter the human body through the skin and
through inhalation (Li et al., 2013).
For instance, the Bayan Obo mine in China, as discussed earlier, is host to
dangerous levels of rare earth contaminants (Huang et al., 2016). These toxins
make their way into living communities through ponds, as discussed earlier,
and through evaporation into the air, where they then fall as precipitation
(Huang et al., 2016). The residents living in villages around Bayan Obo from1999
to 2006 were excessively exposed to these toxins, and 61 individuals died
from lung or brain cancer as a result of this exposure (Huang et al., 2016).
Other nearby residents suffered from respiratory illnesses, cardiovascular
disease, leukemia, osteoporosis, and liver cancer (Huang et al., 2016). These
health effects are the result of the toxins damaging cell walls inside the body,
thereby facilitating damage to multiple organs (Li et al., 2013). Moreover, the
radiation linked to rare earth metals can also have detrimental effects on
human health (Ali, 2014). These harmful effects include skin burns, cancer,
and cardiovascular disease (Ali, 2014). These toxins are also capable of crossing
the placenta in pregnant women, leading to an accumulation of toxins in the
fetus which result in birth defects (Adeel et al., 2019). Thus, it is clear that the
impact of rare earth metals on the environment has major consequences for
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RaRe eaRth Metals: an IntRoductIon
human health, several of which are potentially life-threatening.
The Potential for Remediation of These Toxic Effects
In the foreseeable future, it is certain that we will continue our exploitation
of rare earth metals. However, given the innumerable harmful effects these
metals can have on the environment, animals, and humans, it is necessary to
understand how to remedy these toxic effects. Researchers are now working
on inventing new technologies and recycling routes to decrease the amount
of waste produced, as well as optimizing mining strategies to reduce water
and energy consumption (Huang et al., 2016). One potential way to offset
these effects is by creating a circular supply chain (Haque et al., 2014). The
purpose of this supply chain would be to recycle and reuse the rare earth metals
which are reaching the end of their life cycle (Haque et al., 2014). For example,
recycling rare earth metals from the waste produced in nickel-metal hydride
batteries would allow for these metals to then be reused in the production
of newer products (Haque et al., 2014). The recycling method would lead to
a decreased environmental impact, as well as a reduction in the radioactive
contaminants that end up leaching into our environment from the wastewater (Haque et al., 2014). Effective recycling requires both a physical and
chemical separation technique to separate the rare earth metals from the
scraps (Haque et al., 2014). Furthermore, recycling electronic devices such as
automotive and electronic equipment is not a common practice, especially in
developing countries (Panayotova & Panayotov, 2021). Providing recycling and
collection systems for these materials is necessary, so that these metals do not
end up circulating in our waste (Panayotova & Panayotov, 2021). In addition,
the energy consumption used during the processing of rare earth metals is
a major contributor to the greenhouse gas effect. To reduce their carbon
footprint, industries should implement ways to reduce energy consumption
or to utilize greener means of energy production (Haque et al., 2014). The
mining of rare earth metals has major implications for the environment, as
it can contribute to climate change and global warming, while also negatively
impacting agriculture, and animal and human health (Haque et al., 2014).
As there is an increasing global demand for these elements, understanding
how to mitigate these toxic effects is more necessary now than ever before.
94
Conclusion
Rare earth metals are incredibly important in our modern world. The use of
these elements in creating consumer products such as electric vehicles and
cell phones has had major impacts in the field of electronics and technology.
However, these benefits do not exist without some additional drawbacks. The
procurement of rare earth metals occurs through mining processes, which have
negative effects on the environment in which they are found and processed.
The harmful effects are caused through the spread of contaminated scraps
and waste leftover from the production of these consumer products. These
contaminants end up in the surrounding water supply, agricultural crops,
and aquatic environments. Once these toxins are in our environment, they
have resulting negative effects on the animals and humans who are exposed
to them. Thus, overall, it is evident that the mining of rare earth metals has
severe consequences for the environment, which in turn, poses serious harm
to both animals and humans. However, despite these harmful effects, rare
earth metals provide us with several benefits and have many applications in
our current lives. Thus, it is imperative to learn how to mine these elements
in a safe manner. This concept was discussed in detail earlier in Chapter 8:
What questions do we still have about the rare earth metals? Learning how to
remedy these toxic effects is a significant step in moving towards taking care
of our environment. Furthermore, the remainder of this book will discuss
the current controversies surrounding rare earth metals.
95
WHAT CONTROVERSY IS
THERE SURROUNDING THE
RARE EARTH METALS?
Written By Amir Ala’a
Introduction
Most of the items everyone uses in their day-to-day lives, such as computers
and phones, each contain a specific ingredient in order to continue their
production. These are rare earth metals. Due to their large significance in
everyday life by being part of our consistent use, these metals must be acquired
from industrial manufacturing companies and workers, for example, some
being Lynas Rare Earths, Australian Strategic Materials, Neo Performance
Materials, etc. (Kozak, 2021). When items as vital to our modern life as rare
earth metals are controlled by a small group of manufacturers, it is inevitable
that conf lict will arise.. Chapter 10 of this book focuses on the controversy
surrounding rare earth metals as well as that surrounding the organizations
that bring about these metals. First and foremost however, we must take a
deeper dive into what these metals actually are.
What Are Rare Earth Metals?
Simply put, the rare earth elements are a collection of seventeen chemical elements that appear together in the periodic table. Yttrium and the 16
lanthanide elements make up the group ( lanthanum, cerium, praseodymium,
neodymium, promethium, samarium, europium, gadolinium, terbium,
dysprosium, holmium, erbium, thulium, ytterbium, lutetium, scandium).
All of the rare earth elements are metals, and the group is known as "rare
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RaRe eaRth Metals: an IntRoductIon
Amir Ala’a
earth metals." Since these metals have so many similar characteristics, they
are frequently discovered together in geologic deposits. Even though many
of them are marketed as oxide compounds, they're also known as "rare earth
oxides." (Earth Elements Uses, 2021).
tested by a Malaysian university and an agricultural institute and proven to
be safe (Looi, 2018). Fuziah Salleh is a legislator from Kuantan parlament,
which is 30 kilometres away from the facility. She has been a vocal opponent
of Lynas' work, claiming that the studies have only looked at “CondiSoil’s
effects on plants, but not on the people who eat the plants.” (Looi, 2018).
Gavin Mudd, an environmental engineering professor at RMIT University
in Melbourne, told Al Jazeera that if Lynas did its processing in Australia, it
would then be subject to “a greater degree of environmental assessment and
have to go through much more stringent public consultation.” (Looi, 2018).
Rare earth metals and alloys containing them are found in a variety of everyday products, including computer memory, DVDs, rechargeable batteries,
mobile phones, catalytic converters, magnets, f luorescent lights, and more
(Earth Elements Uses, 2021).For more detailed information about what exactly
the rare earth metals are and how they are used, take a look at chapter 5 of
this book.
Lynas Refinery and Environmental Controversy
Lynas, an Australian-listed business, is now the only significant non-Chinese provider of rare earth elements (Financial Times, 2020). At a facility in
Malaysia, Lynas manufactures light rare earth metals such as praseodymium
and neodymium (Fund Rare-Earth, n.d.). Environmentalists, campaigners,
and the local public have been opposed to the Lynas facility in Malaysia, and
some of them recently went to court in an ultimately failed attempt to stop
Lynas' activities. Their worries were inf luenced in part by what transpired
at a previous rare earth metals refinery at Bukit Merah in Perak, Malaysia.
(Looi, 2018). Residents accused Mitsubishi Chemical, which owns a portion
of the factory, for an increase in birth abnormalities and leukaemia occurrences in the surrounding area. After more than ten years, the factory was
shut down in 1994, and Mitsubishi Chemical has spent an estimated $100
million in order to clean up the site. Lynas dismisses comparisons to Bukit
Merah, claiming that its garbage is considerably less hazardous. According to
Lynas, the residue at Bukit Merah was more than 60 times more radioactive
than the trash produced by the firm (Looi, 2018). Another major source of
worry is the lack of a long-term strategy for dealing with the plant's radioactive waste. Lynas claims it will convert the trash into CondiSoil, a soil
conditioner that will eliminate the need for a permanent disposal facility.
The strategy is said to be “in line with internationally accepted principles of
residue management”. In research funded by Lynas itself, CondiSoil was
98
Lynas and MP Materials
According to a government document obtained by Reuters, the Department
of Defense in the US reevaluated then changed its decision to finance two
projects to process rare earth materials for military weaponry, one of which
has controversial links to China (Scheyder, 2020). Which resulted in the
two companies not getting that financial support and all due to some questionable connections from China which cut all ties with the US and these
companies. Former president Donald Trump's strategy to reconstruct the US
rare earth metals supply chain and minimise reliance on China, the world's
largest supplier of the key minerals required to create a variety of weapons,
has taken a step backward with the Pentagon's decision. Lynas Corp LYC.
AX of Australia and privately held MP Materials of the United States both
announced on April 22 that the Pentagon had given them money for rare
earth separation facilities in Texas and California, respectively (Scheyder,
2020). That same day, Reuters reported that a Chinese company's minority
interest in MP Materials, which controls the sole rare earth metals mine
in the United States, has raised worries among US Department of Energy
experts. Senator Ted Cruz among five other senators addressed a letter to
the Pentagon later that week urging it to finance exclusively US rare earth
metals programmes. According to a letter reviewed by Reuters, the Pentagon notified applicants on April 29 that the decision had been “put on hold
until further research can be conducted.” In a statement put out on Friday,
Lynas further established its conformation with the Pentagon's decision. Any
other requests for comment were not returned by MP Materials (Scheyder,
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Amir Ala’a
2020). The Pentagon intends to proceed with the grant after the extra study
is completed, the paper says. It was unclear what kind of additional study the
military was planning to perform. The award is still under active solicitation,
according to the US military agency in charge of it, which refuses to speak
further on this topic. Other requests for further comment to the Pentagon's
headquarters were not returned. The Pentagon grant was intended to help
with the processing of so-called heavy rare earth metals, a less abundant
form of the material that is widely utilised in weaponry (Scheyder, 2020).
According to USGS statistics, the mines held by Lynas in Australia and MP
Materials in California have relatively small quantities of heavy rare earth
metals, causing some controversy when the two firms announced their
selection last month. Senator Mike Enzi, a strong backer of Rare Element
Resources Ltd REEMF.PK's rare earth elements project in his home state of
Wyoming, and a signatory to the senators' April letter, said he would prefer
Pentagon financing to go to U.S. mines that support a new U.S. rare earth
elements’ supply chain (Scheyder, 2020). According to his spokesperson, Enzi
privately complained to the Pentagon last autumn that it was difficult for
firms to apply for the award and that the application evaluation process was
not transparent once they did. In an attempt to placate Enzi, the Pentagon
extended the deadline, but his home state's rare earth metal project was not
picked. Lynas, the world's largest producer of rare earth metals outside of
China, plans to export rare earth elements from its Western Australian mine
to the Texas plant for final processing. According to Reuters, the Pentagon is
also evaluating proposals for financing for other rare earth-related initiatives.
Applicants have said that they anticipate hearing back in the next few months
(Scheyder, 2020). Although the funds were granted for planning work for the
building of a facility to process the minerals, the amount received was not
made public by the US government. Lynas stated in a statement on Friday
that it will proceed with its initiative. MP Materials did not immediately
respond to a request for comment on whether or not it intends to proceed
with design work on its project (Scheyder, 2020).
inf luence growing as production. China has the world's biggest rare-earth
deposits, accounting for around 37% of worldwide reserves. In comparison,
the United States possesses 1.17 percent of world reserves, while Vietnam and
Brazil both have approximately 18 percent (Hearty, 2019). In 2018, Chinese
companies controlled more than 85% of the supply chain's expensive processing
stage and produced more than 70% of the world's rare-earth-metal supply.
However, as additional companies have joined (or reentered) the market, this is
down from an astounding 97 percent in 2009. Australia and the United States,
the second and third largest producers respectively, generated about 12% and
9% of global rare earth elements (Hearty, 2019). China will boost efforts to
combat illicit rare earth metal mining, manufacturing, and smuggling while
also encouraging more high-end processing, according to new instructions
released on Friday by the Chinese ministry of industry (Staff, 2019).
China and Rare Earth Metals
China is a region that dominates rare-earth production at all levels, with its
100
Despite having owned most of the rare earth metal supply for decades, China
has spent the last decade attempting to “order” the industry by shutting
down illicit mines, limiting exports, and limiting domestic output. Small
private companies have been shuttered, and management of the sector has
been transferred to six state-owned mining corporations (Staff, 2019). The
industry's regulation and oversight has improved, but illicit mining and
manufacturing continued to disturb "market order" and harm legitimate
businesses, according to a notice from the Ministry of Industry and Information Technology (MIIT). MIIT stated that it will increase its efforts to prevent
illicit mining and recycling of rare earth minerals, as well as guaranteeing all
unauthorised operations are shut down (Staff, 2019). It will also implement
a "traceability system" to prevent purchasers from obtaining illicit materials
and to guarantee that manufacturers do not exceed their output targets, as
well as suspending the licences of law-breaking businesses. In key producing
regions like Inner Mongolia and Jiangxi, the rare earth metal business has
polluted huge amounts of land and water, and the ministry has promised to
offer greater help to clean up the sector and minimise waste discharges (Staff,
2019). The ministry stated that it would endeavour to assist the development
of high-end rare earth metal goods and that it would build a new research
centre to promote new uses and boost innovation and competitiveness. In
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Amir Ala’a
2009, China began a crackdown on the rare earth element industry, saying
that illicit operations lowered worldwide prices and made it dif ficult to
afford the high environmental costs of production. Foreign countries, on
the other hand, have accused Beijing of abusing its dominance on global
supply to achieve undue economic and political advantage (Staff, 2019). The
World Trade Organization compelled Beijing to eliminate rare earth element
export limits in 2014, but it continues to limit domestic production for environmental reasons. In 2018, China's yearly limit for rare earth mining was
120,000 tonnes, with a maximum of 115,000 tonnes destined for smelting
and separation (Staff 2019).
as leverage in the trade conf lict. In May 2019, President Xi paid a visit to JL
Mag, a key manufacturer of rare earth metal-based permanent magnets,
exacerbating these concerns. Wang Shouwen, China's deputy commerce
minister, emphasised: “If some countries use China’s rare earth metals to
produce products to contain China’s development, this is unacceptable by
standards of both minds and hearts” (Schmid, 2019). The Chinese National
Development and Reform Commission (NDRC) has stated that it intends to
tighten controls on rare earth metal exports. Several communist-leaning
publications have also reported that the Chinese government is seriously
contemplating banning rare earth element shipments to the United States
(Schmid, 2019).
US and China Dispute
The trade war between the United States and China had escalated to the point
where export limits on rare earth elements are being considered as a possible
penalty by the Chinese government(Schmid, 2019). This contribution provided
a concise analysis of the United States' current reliance on rare earth metals
from China, drawing parallels to events that occurred during the rare earth
metal crisis of 2010 and 2011, which was triggered by geopolitical tensions
between Japan and China. There are many risks connected with limitations
on the trading of rare earth metals (Schmid, 2019). Some findings say Europe
could have been affected as well, and it should be better equipped to deal with
rare earth supply shortages. In May 2019, the US administration boosted
tariffs on Chinese imports worth $200 billion from ten percent to twenty-five
percent. China retaliated by imposing retaliatory taxes on US products. The
original list, which covered items worth $50 billion in 2018, was expanded
to include goods worth another $60 billion in June 2019 (Schmid, 2019).
Import taxes on US items worth 110 billion dollars have now been imposed,
making nearly all exports from the United States to China subject to tariffs.
China is unable to keep up with the quantity of products subject to tariffs
due to the US trade imbalance, which reached 420 billion dollars in 2018, as
the US is one of China’s largest import markets(Schmid, 2019). While there
were early signs of progress in the trade dispute between the US and China
in October 2019, China also stated that it may seriously consider using its
market strength in rare earth metal production and the US's reliance on it
102
Conclusion
In the long run, being a company that revolves around products that encompass our daily lifestyles will of course have much controversy for many reasons.
Some corporations that focus on rare earth metals are Lynas Rare Earths,
Australian Strategic Materials, and Neo Performance Materials. (Kozak,
2021). Problems occur in these businesses mostly due to environmental
issues, and economic sanctions caused by global trade wars.. However, that
is not to say that all controversy within this industry is negative. Concerns
about negligent environmental practices, for example, are useful to bring up
although they may cause harm to the industry. . In the end, bigger harms
are caused to the industry by the improper reactions of major producers of
these metals to controversy, rather than the controversy itself.
103
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