Specimens

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

Clear, pure cleavages, Mohs’ hardness of 2.

Feldspar group; pink cleavages showing perthitic texture, common potassium feldspar, Mohs’ hardness of 6.

Cleaned, pure, bright, metallic native copper.

Brown, fluorescent crystals intergrown in dolomite rock.

Clear, euhedral points and sections.

Pure kaolinite powder, 200 mesh.

Deep blue, massive, with nepheline; key feldspathoid.

Amphibole group; black, coarse, massive.

Bright metallic cubic cleavages; lead ore.