Selenite
Real mineral · common · CaSO₄·2H₂O
The transparent crystalline variety of gypsum. Forms in evaporite sequences and in cave environments where calcium sulfate solutions precipitate slowly. Can grow into metre-scale crystals in stable underground conditions.
Identity
- Formula
- CaSO₄·2H₂O
- Chemical class
- sulfate
- Also known as
- Satin spar (fibrous variety), Desert rose (rosette habit), Gypsum (parent mineral)
Crystallography
- Crystal system
- monoclinic
- Habits
- tabular, prismatic, massive
- Fracture
- fibrous
Physical properties
- Mohs hardness
- 2
- Density
- 2.32 g/cm³
- Luster
- vitreous, pearly
- Colors
- colorless, white, gray
- Streak
- white
- Transparency
- transparent, translucent
Geology
- Origins
- sedimentary
- Host rocks
- evaporite deposits, limestone
- Associated minerals
- Halite, Calcite, Anhydrite
- Geography
- Mexico, USA, Morocco, Russia, UK
Classification
- Rarity
- common
- Gem quality
- No
Arcane properties
- Affinity
- light, arcane
- Effects
- warding, scrying
- Planar origin
- Material Plane
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