"Gary K. Besonson"

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

Coarse-grained, with microcline, biotite and horblende phenocrysts.

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

Cut black mica cleavage sheets.

Deep purple crystal clusters.

Well-cemented, medium-grained orthoquartzite.

An alternative to a ballistic pendulum designed to demonstrate the conservation of momentum.

Good grade, brass-yellow copper ore, massive.

Black, fissile; commonly with carbonized fossil plant impressions.

White, massive, coarse crystalline vein, Mohs’ hardness of 7.

Red, medium, to coarse-grained iron oxide cement; shows hematite bands.

Cleaned, pure, bright, metallic native copper.

Gray with line crinoid columnal fragments.

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

Pure, white, earthy “China clay”.

Pink and gray bands, with biotite; shows good foliation.