atural dyeing—the practice of extracting pigments from plants, bugs and other things of the earth to colour cloth—is a difficult art. Its materials are notoriously unruly, requiring formulas so precise they approach science: a hair difference in weight shifts the colour a shade; a slight change in acidity flubs the texture—the dye bath is a well of rebellion. But to Crystal Lee, 30, artist and self-dubbed soul behind Project Coal, ceding control to nature is a matter of course. She takes care not to