Image: <bdi><a href="https://www.wikidata.org/wiki/Q56247090" class="extiw" title="d:Q56247090"><span title="mineral collector and dealer">Robert M. Lavinsky</span></a></bdi> (CC BY-SA 3.0)
monocliniccommonSulfates
Gypsum
CaSO₄·2H₂O
This image displays a transparent to translucent, colorless crystal of gypsum, specifically the selenite variety, exhibiting well-defined crystal forms and possibly twinning. The crystal appears blocky with smooth faces.
Gypsum Physical Properties
Mohs Hardness
1.5Crystal System
monoclinicLuster
vitreousStreak Color
whiteCleavage
perfect on {010}, distinct on {100} and {111}Fracture
unevenSpecific Gravity
2.32Colors
colorless, white, gray, yellow, red, brownTransparency
transparentType Locality
Red River Floodway, WinnipegMineral Group
SulfatesUses
plaster of Paris, drywall, fertilizer, cement, ornamental stone, collectorAssociated Minerals
halite, sulfur, calcite, dolomite, anhydrite, celestiteRarity
commonGeological Context
Gypsum is a common evaporite mineral that forms in sedimentary environments, typically from the precipitation of calcium sulfate in evaporating saline waters such as shallow marine basins, lagoons, or saline lakes.
