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monocliniccommonSulfates
Selenite
CaSO4•2H2O
This is a large, clear, and generally colorless blade of selenite, which is a cleavage fragment from a larger crystal, measuring 32 cm long.
Selenite Physical Properties
Mohs Hardness
2Crystal System
monoclinicLuster
vitreousStreak Color
whiteCleavage
Perfect in one direction (pinacoidal), distinct in two othersFracture
conchoidalSpecific Gravity
2.32Colors
clear, colorlessTransparency
transparentType Locality
UtahMineral Group
SulfatesUses
industrial, sculpture, collector, jewelryAssociated Minerals
halite, sulfur, calcite, dolomite, anhydriteRarity
commonGeological Context
Selenite, a variety of gypsum, is a common evaporite mineral that forms from the precipitation of calcium sulfate from saline waters, often found in sedimentary deposits, caves, and as a secondary mineral.
