"Dessus de bouchon"

A classroom set that covers the major types of coal.

Pure kaolinite powder, 200 mesh.

Exemplary display of hexoctahedral crystal shape.

Deep purple crystal clusters.

Light pink, massive, crystalline, translucent.

Nearly pure, green crystalline forsterite.

Pure, bright yellow, Frasch sulfur.

Brown, earthy, massive; used for yellow pigment.

Pyroxene group; dark green, pure cleaved fragments.

Feldspar group; white-to-gray cleavages of sodic plagioclase; some show twinning.