Mineralogical Magazine (2020), 1–5
doi:10.1180/mgm.2020.5
IMA Commission on New Minerals, Nomenclature and Classification (CNMNC)
Newsletter 53
Ritsuro Miyawaki (Chairman CNMNC)1, Frédéric Hatert (Vice-Chairman CNMNC)2, Marco Pasero (Vice-Chairman
CNMNC)3* and Stuart J. Mills (Secretary CNMNC)4
1
Department of Geology and Paleontology, National Museum of Nature and Science, 4-1-1 Amakubo, Tsukuba 305-0005, Japan –
[email protected];
Laboratoire de Minéralogie, Université de Liège, B-4000 Liège, Belgium –
[email protected]; 3 Dipartimento di Scienze della Terra, Università di Pisa, Via Santa Maria
53, I-56126 Pisa, Italy –
[email protected]; and 4 Geosciences, Museums Victoria, PO Box 666, Melbourne, Victoria 3001, Australia –
[email protected]
2
The information given here is provided by the IMA Commission on New Minerals, Nomenclature and Classification for comparative
purposes and as a service to mineralogists working on new species.
Each mineral is described in the following format:
Mineral name, if the authors agree on its release prior to the full description appearing in press
Chemical formula
Type locality
Full authorship of proposal
E-mail address of corresponding author
Relationship to other minerals
Crystal system, Space group; Structure determined, yes or no
Unit-cell parameters
Strongest lines in the powder X-ray diffraction pattern
Type specimen repository and specimen number
Citation details for the mineral prior to publication of full description
Citation details concern the fact that this information will be published in the Mineralogical Magazine on a routine basis, as well
as being added month by month to the Commission’s web site.
It is still a requirement for the authors to publish a full description of the new mineral.
NO OTHER INFORMATION WILL BE RELEASED BY THE COMMISSION
NEW MINERAL PROPOSALS APPROVED IN DECEMBER 2019
IMA No. 2019-082
Dutrowite
Na(Fe2+
2.5Ti0.5)Al6(Si6O18)(BO3)3(OH)3O
Fornovolasco metarhyolite formation, close to the Boscaccio
locality, Fornovolasco, Fabbriche di Vergemoli (LU), Apuan
Alps, Tuscany, Italy (44°01’53”N, 10°22’11”E)
Cristian Biagioni*, Ferdinando Bosi, Daniela Mauro, Henrik
Skogby, Andrea Dini and Federica Zaccarini
*E-mail:
[email protected]
Tourmaline supergroup
Trigonal: R3m; structure determined
a = 15.9864(8), c = 7.2187(4) Å
6.40(42), 4.61(18), 4.24(52), 4.00(60), 2.971(61), 2.585(100),
2.048(41), 1.925(24)
*Author for correspondence: Marco Pasero, Email:
[email protected]
Cite this article: Miyawaki R., Hatert F., Pasero M. and Mills S.J. (2020) IMA
Commission on New Minerals, Nomenclature and Classification (CNMNC) —
Newsletter 53. Mineralogical Magazine 1–5. https://doi.org/10.1180/mgm.2020.5
© Mineralogical Society of Great Britain and Ireland 2020
Type material is deposited in the mineralogical collections of
the Museo di Storia Naturale, Università di Pisa, Via Roma
79, Calci (PI), Italy, catalogue number 19890
How to cite: Biagioni, C., Bosi, F., Mauro, D., Skogby, H.,
Dini, A. and Zaccarini, F. (2020) Dutrowite, IMA 2019-082.
CNMNC Newsletter No. 53; Mineralogical Magazine, 84,
https://doi.org/10.1180/mgm.2020.5
IMA No. 2019-083
Fluorapophyllite-(NH4)
(NH4)Ca4(Si8O20)F⋅8H2O
Vechec andesite quarry, 2.8 km SW of the Vechec village,
Vranov nad Topľou Co., Prešov Region, Slovakia (48°
51’09.58”N, 21°36’12.10”E)
Martin Števko*, Jiří Sejkora, Jakub Plášil, Zdeněk Dolníček and
Radek Škoda
*E-mail:
[email protected]
Apophyllite group
Tetragonal: P4/mnc; structure determined
a = 8.99336(9), c = 15.7910(3) Å
2
Ritsuro Miyawaki et al.
7.897(31), 7.812(13), 4.547(14), 3.946(100), 2.985(39), 2.484(11),
2.010(10), 1.579(12)
Type material is deposited in the collections of the Department
of Mineralogy and Petrology, National Museum in Prague,
Cirkusová 1740, 19300 Praha 9, Czech Republic, catalogue
number P1P 44/2019
How to cite: Števko, M., Sejkora, J., Plášil, J., Dolníček, Z. and
Škoda, R. (2020) Fluorapophyllite-(NH4), IMA 2019-083.
CNMNC Newsletter No. 53; Mineralogical Magazine, 84,
https://doi.org/10.1180/mgm.2020.5
IMA No. 2019-085
Liraite
3+ 2+
2+
NaCa2Mn2+
2 [Fe Fe ]Mn2 (PO4)6(H2O)2
Ceferino Namuncurá pegmatite, Pocho Department, Córdoba
Province, Argentina (31°37’45”, 65°15’03”W)
Marco E. Biglia*, Mark A. Cooper, Edward S. Grew, Jorge
A. Sfragulla, María F. Márquez-Zavalía, Alina B. Guereschi,
Martin G. Yates and Miguel A. Galliski
*E-mail:
[email protected]
Wicksite group
Orthorhombic: Pcab; structure determined
a = 12.608(6), b = 12.918(6), c = 11.737(4) Å
3.170(22), 2.927(49), 2.856(65), 2.821(25), 2.769(26), 2.745
(100), 2.706(30), 2.097(29)
Type material is deposited in the collections of the Mineralogy
and Geology “Dr. A. Stelzner” Museum, Av. Vélez Sársfield
249, X5000JJC Córdoba, Argentina, catalogue n. MS003457
How to cite: Biglia, M.E., Cooper, M.A., Grew, E.S., Sfragulla,
J.A., Márquez-Zavalía, M.F., Guereschi, A.B., Yates, M.G. and
Galliski, M.A. (2020) Liraite, IMA 2019-085. CNMNC
Newsletter No. 53; Mineralogical Magazine, 84, https://doi.
org/10.1180/mgm.2020.5
IMA No. 2019-086
Arrheniusite-(Ce)
CaMg[(Ce7Y3)Ca5](SiO4)4(Si2B3AsO18)(BO3)F11
Östanmossa mine, Norberg Municipality, Västmanland
County, Sweden (60°05’N, 15°56’E, 130 m asl)
Dan Holtstam*, Luca Bindi, Hans-Jürgen Förster, Paola
Bonazzi and Ulf B. Andersson
*E-mail:
[email protected]
The Mg-As analogue of hundholmenite-(Y)
Trigonal: R3m; structure determined
a = 10.8082(3), c = 27.5196(9) Å
7.739(24), 4.431(43), 3.146(51), 3.010(100), 2.976(70),
2.954(32), 2.702(46), 1. 848(24)
Type material is deposited in the mineralogical collections of
the Department of Geosciences, Swedish Museum of Natural
History, Box 50007, SE-10405 Stockholm, Sweden, collection
number GEO-NRM #19540155
How to cite: Holtstam, D., Bindi, L., Förster, H.-J., Bonazzi,
P. and Andersson, U.B. (2020) Arrheniusite-(Ce), IMA
2019-086. CNMNC Newsletter No. 53; Mineralogical
Magazine, 84, https://doi.org/10.1180/mgm.2020.5
IMA No. 2019-087
Seaborgite
LiK2Na6(UO2)(SO4)5(SO3OH)(H2O)
Blue Lizard mine, Red Canyon, White Canyon District, San
Juan Co., Utah, USA (37°33’26”N, 110°17’44”W)
Anthony R. Kampf*, Travis A. Olds, Jakub Plášil, Joe Marty,
Samuel N. Perry, Loretta Corcoran and Peter C. Burns
*E-mail:
[email protected]
New structure type
Triclinic: P1; structure determined
a = 5.4511(4), b = 14.487(1), c = 15.873(1) Å, α = 76.295(5),
β = 81.439(6), γ = 85.511(6)°
14.67(97), 5.320(100), 5.093(67), 4.733(75), 3.489(65),
3.331(61), 3.078(61), 2.954(98)
Type material is deposited in the mineralogical collections of
the Natural History Museum of Los Angeles County, 900
Exposition Boulevard, Los Angeles, CA 90007, USA, catalogue
number 74163
How to cite: Kampf, A.R., Olds, T.A., Plášil, J., Marty, J., Perry,
S.N., Corcoran, L. and Burns, P.C. (2020) Seaborgite, IMA
2019-087. CNMNC Newsletter No. 53; Mineralogical
Magazine, 84, https://doi.org/10.1180/mgm.2020.5
IMA No. 2019-088
Adanite
Pb2(Te4+O3)(SO4)
North Star mine, Mammoth, Tintic district, Juab Co., Utah,
USA (39°55’14”N, 112°06’24”W – holotype); Tombstone,
Cochise Co., Arizona, USA (cotype)
Anthony R. Kampf*, Robert M. Housley, George R. Rossman,
Hexiong Yang and Robert T. Downs
*E-mail:
[email protected]
Known synthetic analogue
Monoclinic: P21/n; structure determined
a = 7.3830(3), b = 10.7545(5), c = 9.3517(7) Å, β = 111.500(8)°
6.744(47), 3.454(80), 3.301(100), 3.114(42), 3.048(73),
2.803(41), 2.745(44), 1.752(45)
Type material is deposited in the mineralogical collections of
the Natural History Museum of Los Angeles County, 900
Exposition Boulevard, Los Angeles, CA 90007, USA, catalogue
number 67505 (holotype), and the RRUFF Project, University
of Arizona, USA, deposition number R190033 (cotype)
How to cite: Kampf, A.R., Housley, R.M., Rossman, G.R., Yang,
H. and Downs, R.T. (2020) Adanite, IMA 2019-088. CNMNC
Newsletter No. 53; Mineralogical Magazine, 84, https://doi.org/
10.1180/mgm.2020.5
IMA No. 2019-089
Celleriite
□(Mn2+
2 Al)Al6(Si6O18)(BO3)3(OH)3(OH)
Rosina pegmatite, San Piero in Campo, Campo nell’Elba (LI),
Elba Island, Tuscany, Italy
Ferdinando Bosi*, Federico Pezzotta, Alessandra Altieri,
Giovanni B. Andreozzi, Paolo Ballirano and Gioacchino
Tempesta
*E-mail:
[email protected]
Tourmaline supergroup
Trigonal: R3m; structure determined
a = 15.9518(4), c = 7.1579(2) Å
6.345(45), 4.210(60), 3.983(88), 3.453(55), 2.942(55),
2.573(100), 2.036(38), 1.913(26)
Type material is deposited in the mineralogical collections of
the Museo Universitario di Scienze della Terra, Sapienza
Università di Roma, P.le Aldo Moro, 5, 00185 Roma, Italy, catalogue number 33287/403 (holotype), and the Museo Civico di
Storia Naturale, Corso Venezia 55, 20121 Milano, Italy, catalogue number M38847 (cotype)
3
Mineralogical Magazine
How to cite: Bosi, F., Pezzotta, F., Altieri, A., Andreozzi, G.B.,
Ballirano, P. and Tempesta, G. (2020) Celleriite, IMA
2019-089. CNMNC Newsletter No. 53; Mineralogical
Magazine, 84, https://doi.org/10.1180/mgm.2020.5
IMA No. 2019-090
Grammatikopoulosite
NiVP
Agios Stefanos mine, ca. 10 km S of the Domokos village,
Othrys ophiolite, Greece (39°04’59”N, 22°25’59”E)
Luca Bindi*, Federica Zaccarini, Elena Ifandi, Basilios
Tsikouras, Chris J. Stanley, Giorgio Garuti and Daniela Mauro
*E-mail:
[email protected]
Structurally related to florenskyite
Orthorhombic: Pnma; structure determined
a = 5.8893(8), b = 3.5723(4), c = 6.8146(9) Å
2.950(20), 2.785(25), 2.273(60), 2.157(100), 2.118(25),
1.915(15), 1.824(15), 1.784(20)
Type material is deposited in the mineralogical collections of
the Museo di Storia Naturale, Università di Pisa, Via Roma
79, Calci (PI), Italy, catalogue number 19911
How to cite: Bindi, L., Zaccarini, F., Ifandi, E., Tsikouras, B.,
Stanley, C.J., Garuti, G. and Mauro, D. (2020)
Grammatikopoulosite, IMA 2019-090. CNMNC Newsletter
No. 53; Mineralogical Magazine, 84, https://doi.org/10.1180/
mgm.2020.5
IMA No. 2019-091
Ellinaite
CaCr2O4
In paralavas in the Halamish and Zohar wadi, southern part of
the Hatrurim Basin, Israel (31°09’47”N, 35°17’57”E – holotype); as mineral phase of an inclusion within diamond, collected from gravels of the Sorriso Creek, a tributary of Rio
Aripuanã, Mato Grosso State, Brazil (11°20’S, 59°11’W –
cotype).
Victor V. Sharygin*, Sergey N. Britvin, Felix V. Kaminsky,
Richard Wirth, Elena N. Nigmatulina, Grigory A. Yakovlev,
Konstantin A. Novoselov and Mikhail N. Murashko
*E-mail:
[email protected]
The Cr analogue of harmunite
Orthorhombic: Pnma; structure determined
a = 8.868(9), b = 2.885(3), c = 10.355(11) Å
4.434(23), 2.589(54), 2.567(100), 2.424(69), 2.418(62),
2.148(34), 1.767(35), 1.758(22)
Type material is deposited in the collections of the Fersman
Mineralogical Museum, Russian Academy of Sciences,
Leninskiy Prospekt 18-2, Moscow 119071, Russia, registration
number 5439/1 (holotype), the Central Siberian Geological
Museum, V.S.Sobolev Institute of Geology and Mineralogy,
Siberian Branch of the RAS, prospekt Akademika Koptyuga
3, Novosibirsk 630090, Russia, catalogue number VII-102/1
(holotype), and the Vernadsky Institute of Geochemistry and
Analytical Chemistry, Kosygin St. 19, Moscow 119334,
Russia, F.V. Kaminsky collection, catalogue number 8/108
(cotype)
How to cite: Sharygin, V.V., Britvin, S.N., Kaminsky, F.V.,
Wirth, R., Nigmatulina, E.N., Yakovlev, G.A., Novoselov, K.A.
and Murashko, M.N. (2020) Ellinaite, IMA 2019-091.
CNMNC Newsletter No. 53; Mineralogical Magazine, 84,
https://doi.org/10.1180/mgm.2020.5
IMA No. 2019-029a
Michitoshiite-(Cu)
Rh(Cu1-xGex)
0 < x ≤ 0.5
Haraigawa, Misato machi, Kumamoto Prefecture, Kyushu,
Japan
Takahiro Tanaka*, Tadashi Shinmachi, Kota Kataoka and
Daisuke Nishio-Hamane
*E-mail:
[email protected]
CsCl-type structure
Cubic: Pm3m
a = 2.977(1) Å
2.103(100), 1.717(3), 1.487(15), 1.332(6), 1.216(70)
Type material is deposited in the mineralogical collections of
the National Museum of Nature and Science, Tsukuba, Japan,
specimen number NSM-46298 (holotype) and NSM-16299
(cotype)
How to cite: Tanaka, T., Shinmachi, T., Kataoka, K. and
Nishio-Hamane, D. (2020) Michitoshiite-(Cu), IMA
2019-029a. CNMNC Newsletter No. 53; Mineralogical
Magazine, 84, https://doi.org/10.1180/mgm.2020.5
NEW MINERAL PROPOSALS APPROVED IN JANUARY 2020
IMA No. 2019-093
Hagstromite
Pb8Cu2+(Te6+O6)2(CO3)Cl4
SW Cut (35°16’20”N, 116°06’04”W – holotype) and Bird Nest
drift (35°16’36”N, 116°06’01”W – cotype), Otto Mountain, 2.5
km WNW of Baker, San Bernardino Co., California, USA
Anthony R. Kampf*, Robert M. Housley, Stuart J. Mills, George
R. Rossman and Joe Marty
*E-mail:
[email protected]
New structure type
Orthorhombic: Ibam; structure determined
a = 23.688(17), b = 9.026(8), c = 10.461(8) Å
3.927(80), 3.423(26), 3.286(44), 2.967(100), 2.601(70),
2.230(23), 1.964(66), 1.846(19)
Type material is deposited in the mineralogical collections of
the Natural History Museum of Los Angeles County, 900
Exposition Boulevard, Los Angeles, CA 90007, USA, catalogue
numbers 73596 (holotype) and 73597 (cotype)
How to cite: Kampf, A.R., Housley, R.M., Mills, S.J., Rossman,
G.R. and Marty, J. (2020) Hagstromite, IMA 2019-093.
CNMNC Newsletter No. 53; Mineralogical Magazine, 84,
https://doi.org/10.1180/mgm.2020.5
IMA No. 2019-095
Waipouaite
Ca3V4+
5 O9[Si2O5(OH)2][Si3O7(OH)2]⋅11H2O
Aranga Quarry, Aranga, Kaipara District, Northland Region,
New Zealand (35°44’06”S, 173°34’47”E)
Peter Elliott* and Anthony R. Kampf
*E-mail:
[email protected]
New structure type
Monoclinic: P21/c; structure determined
a = 12.843(3), b = 23.589(5), c = 11.560(2) Å, β = 115.54(3)°
11.78(100), 9.54(16), 7.85(19), 6.29(32), 5.92(31), 5.22(21),
3.140(18), 2.850(17)
Type material is deposited in the mineralogical collections of
the South Australian Museum, North Terrace, Adelaide,
South Australia 5000, Australia, registration number G34802
4
Ritsuro Miyawaki et al.
How to cite: Elliott, P. and Kampf, A.R. (2020) Waipouaite,
IMA 2019-095. CNMNC Newsletter No. 53; Mineralogical
Magazine, 84, https://doi.org/10.1180/mgm.2020.5
IMA No. 2019-096
Eliopoulosite
V7S8
Agios Stefanos mine, ca. 10 km S of the Domokos village,
Othrys ophiolite, Greece (39°04’59”N, 22°25’59”E)
Luca Bindi*, Federica Zaccarini, Paola Bonazzi, Tassos
Grammatikopoulos, Basilios Tsikouras, Chris J. Stanley and
Giorgio Garuti
*E-mail:
[email protected]
Known synthetic analogue
Trigonal: P3221; structure determined
a = 6.689(3), c = 17.403(6) Å
2.896(29), 2.591(45), 2.049(100), 1.672(40), 1.608(10),
1.296(20), 1.096(15), 1.024(12)
Type material is deposited in the mineralogical collections of
the Museo di Storia Naturale, Università di Pisa, Via Roma
79, Calci (PI), Italy, catalogue number 19911
How to cite: Bindi, L., Zaccarini, F., Bonazzi, P.,
Grammatikopoulos, T., Tsikouras, B., Stanley, C.J. and Garuti,
G. (2020) Eliopoulosite, IMA 2019-096. CNMNC Newsletter
No. 53; Mineralogical Magazine, 84, https://doi.org/10.1180/
mgm.2020.5
IMA No. 2019-097
Kesebolite-(Ce)
CeCa2Mn(AsO4)(SiO3)3
Kesebol Mn-(Fe-Cu) deposit, Åmål municipality, Västra
Götaland, Sweden (58°59’04”N, 12°31’47”E, 130 m asl)
Dan Holtstam*, Luca Bindi, Andreas Karlsson, Jörgen Langhof,
Thomas Zack, Paola Bonazzi and Anders Persson
*E-mail:
[email protected]
New structure type
Monoclinic: P21/c; structure determined
a = 6.7382(3), b = 13.0368(6), c = 12.0958(6) Å, β = 98.578(2)°
6.50(22), 5.96(54), 5.70(42), 3.228(58), 3.138(84), 3.114(100),
2.924(84), 2.908(63)
Type material is deposited in the mineralogical collections of
the Department of Geosciences, Swedish Museum of Natural
History, Box 50007, SE-10405 Stockholm, Sweden, collection
number GEO-NRM #20100343
How to cite: Holtstam, D., Bindi, L., Karlsson, A., Langhof, J.,
Zack, T., Bonazzi, P. and Persson, A. (2020) Kesebolite-(Ce),
IMA 2019-097. CNMNC Newsletter No. 53; Mineralogical
Magazine, 84, https://doi.org/10.1180/mgm.2020.5
IMA No. 2019-099
Ramosite
Pb25.7Sn8.3Mn3.4Sb6.4S56.2
Uchucchacua polymetallic deposit, Oyon district, Catajambo,
Lima Department, Peru (10°37’23”S, 76°41’17”W)
Frank N. Keutsch*, Shao-Liang Zheng, Dan Topa and Chris
Stanley
*E-mail:
[email protected]
The Mn analogue of franckeite
Monoclinic: C2/m (Q-slab), P21 (H-slab)
a = 5.82, b = 5.92, c = 17.65 Å, β = 99.1° (Q-slab)
a = 6.23, b = 3.69, c = 17.59 Å, β = 93.3° (H-slab)
3.48–3.59(58), 3.23–3.32(13), 3.13–3.20(4), 2.86–3.09(100),
2.54–2.59(7), 2.36–2.42(14), 2.18–2.25(73), 1.96–2.07(43)
Type material is deposited in the mineralogical collections of
the Naturhistorisches Museum, Burgring 7, 1010 Wien,
Austria, catalogue number O1798, and the Mineralogical &
Geological Museum, Harvard University, Cambridge, MA
02138, USA, specimen numbers 2019.18.1 and 2019.18.2
How to cite: Keutsch, F.N., Zheng, S.-L., Topa, D. and Stanley,
C. (2020) Ramosite, IMA 2019-099. CNMNC Newsletter No.
53; Mineralogical Magazine, 84, https://doi.org/10.1180/mgm.
2020.5
NOMENCLATURE/CLASSIFICATION PROPOSALS APPROVED
IN DECEMBER 2019
IMA 19-G: discreditation of ferrotellurite
Proposal 19-G is accepted, and the ill-defined mineral ferrotellurite is discredited. Indeed, this species has been shown to
be equivalent to keystoneite, Mg0.5NiFe3+(Te4+O3)3⋅4.5H2O.
IMA 19-H: discreditation of heliophyllite
Proposal 19-H is accepted, and heliophyllite is discredited.
This species is identical to ecdemite, Pb6As2O7Cl4.
REVISED CHEMICAL FORMULA
A paper on the mineral ilmajokite has been recently published
[IUCrJ, 7 (2020), 121–128] in which the ideal chemical formula
of the mineral is given as Na11KBaCe2Ti12Si37.5O94(OH)31⋅29H2O.
With respect to the previously accepted formula, there is a new
chemical element (K); moreover Ba and Ce, which were previously
put together with Na as subordinate cations, now acquire the status
of species-forming constituents, as the structural study clearly indicates that they are partitioned at specific crystallographic sites. These
data were examined carefully by the CNMNC officers and were considered reliable. Accordingly it was agreed to modify the formula of
the mineral in the official IMA List of Minerals. Moreover, the
occurrence of a REE as a species-forming element implies the
renaming of ilmajokite to ilmajokite-(Ce).
ERRATUM
The file on the new mineral petrovite in CNMNC Newsletter 52
was wrong in the following details: IMA No.; chemical formula;
full authorship of proposal; unit-cell parameters; strongest lines
in the X-ray powder diffraction pattern; citation details for the
mineral prior to publication of full description. Here is the correct
version.
IMA No. 2018-149b
Petrovite
Na6Cu(SO4)4
Second scoria cone of the Northern Breakthrough of the Great
Tolbachik fissure eruption, Tolbachik volcano, Kamchatka,
Far-Eastern Region, Russia (55°41’N, 160°14’E, 1200 m asl)
Stanislav K. Filatov*, Andrey P. Shablinskii, Lidiya
P. Vergasova, Sergey V. Krivovichev and Svetlana V. Moskaleva
*E-mail:
[email protected]
Chemically similar to saranchinaite
Monoclinic: P21/c; structure determined
a = 12.6346(8), b = 9.0760(6), c = 12.7560(8) Å, β = 108.75(9)°
7.24(100), 6.25(38), 4.47(31), 3.70(36), 3.65(34), 2.837(28),
2.600(48), 2.571(37)
Mineralogical Magazine
Type material is deposited in the collections of the
Mineralogical Museum of Saint-Petersburg State University,
University Emb. 7/9, St. Petersburg 199034, Russia, catalogue
number 1/19696
5
How to cite: Filatov, S.K., Shablinskii, A.P., Vergasova, L.P.,
Krivovichev, S.V. and Moskaleva, S.V. (2020) Petrovite, IMA
2018-149b. CNMNC Newsletter No. 53; Mineralogical
Magazine, 84, https://doi.org/10.1180/mgm.2020.5