"The Mystery of Lyle and Louise"

Utah

Spinel group; black, dull metallic luster; common iron oxide.

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

Brownish gray, translucent.

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

Brown, earthy, massive; used for yellow pigment.

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

Nearly pure, green crystalline forsterite.

Light pink, massive, crystalline, translucent.

Light gray, compact, hard, opaque, microcrystalline silica mineral.