CaSO4Orthorhombic
Anhydrite
CaSO4
SulfatesChemical FormulaCaSO4
Crystal SystemOrthorhombic
Mohs Hardness3.5
Specific Gravity2.97
ColorColorless, white, blue, gray
LusterVitreous to pearly
StreakWhite
CleavageThree directions
FractureUneven
Occurrence
Found in evaporite deposits. Dehydrated form of gypsum. Used in cement.