Gypsum

Gypsum

Gypsum,  CaSO4 . 2H2O  Calcium Sulphate dihydrate, is an evaporite mineral. This specimen was formed as a saline residue arising from the evaporation of an enclosed basin of sea water. Of the two specimens, one appears to be a loose aggregate, and the smaller one has obvious layering. The location is loosely given as Crete.