"Avantor"

Feldspar group; good cleavages of pure soda lime feldspar; most show twinning and labradorescence.

Good grade, brass-yellow copper ore, massive.

Brown, fluorescent crystals intergrown in dolomite rock.

Amphibole group; dark greenish black cleavages, somewhat columnar.

Red, earthy, in natural chunk form; common pigment ore.

Bright blue crystalline veins and coatings in a matrix of mixed copper ore.

Pure kaolinite powder, 200 mesh.

Classic “peacock” aluminum ore.

Cut black mica cleavage sheets.

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

A classroom set that covers the major types of coal.

Clear rhombs showing double refraction.

Classic, white chalk, massive; from Cliffs of Dover, England.

Crystals and crystal sections up to 1", Mohs’ hardness of 9.

Pure, large, transparent-to-translucent cleavages, Mohs’ hardness of 4.

Bright metallic cubic cleavages; lead ore.