Identification Malachite Identification Sheet A bright green copper carbonate recognized by its color, concentric banding, botryoidal habit, and effervescence in acid.
Identification Rhodochrosite Identification Sheet Colorado's rose-pink state mineral: a manganese carbonate identified by color, low hardness, rhombohedral cleavage, and a warm-acid react…
Identification Onyx Identification Sheet A banded chalcedony with a parallel-layered structure, a hardness that outlasts most imposters, and — in this particular library — a name…
