"Classroom Mineral Specimens"

Yellow to orange crystal with a glassy luster and smooth, often transparent appearance.

Feldspar group; greenish gray alkali feldspar, coarse crystalline, some iridescence.

Feldspar group; white to gray, sodium plagioclase cleavages; some faces may show twinning.

Cut black mica cleavage sheets.

Pyroxene group; dark green, pure cleaved fragments.

Pure translucent to white, rhombic cleavages, Mohs’ hardness of 3.

Fresh Green forsterite, classic “twin sisters” dunite.

Deep blue, massive, with nepheline; key feldspathoid.

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

White, fibrous, silky luster.

Good grade, green, massive; copper ore.

White, fine, massive, opaque to slightly translucent.

Feldspar group; calcium end member plagioclase crystals in pyroxene matrix.

Amphibole group; black, coarse, massive.

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

Amphibole group; dark greenish black cleavages, somewhat columnar.