Mineral Species:  Calcite

Chemical Formula: CaCO3

Chemical Name: Calcium Carbonate

Mineral Class: Carbonate

Mineral Notes:  Calcite is one of the commonest minerals, being the main constituent of limestone. The mineral will bubble in acid distinguishing it from many similar species, even other carbonates which do not dissolve so easily in cold acids.

Description: A brown matrix whose upper surface is covered by several fused white Calcite crystals. Whilst most are opaque, the largest, and best formed, has an almost optical quality. Superb play of irridescent colours on the surface.

Location: Areponapuchic Canyon, Chihuahua, Mexico.