Mineral Species: Gypsum on Psilomelane

Chemical Formula: CaSO4.2H2O

Chemical Name: Hydrous Calcium Sulfate

Mineral Class: Sulfate

Mineral Notes:  Gypsum is the commonest sulfate. It is a major rock forming mineral that forms massive beds, usually from precipitation from highly saturated waters. Since it forms easily from saline water, Gypsum may have many inclusions of other minerals and even trapped bubbles of air and water.