mineral

Gypsum (Desert Rose or Selenite variety)

Calcium Sulfate Dihydrate (CaSO4·2H2O)

AI-generated identification · may be incorrect

Hardness: 2 on Mohs scale (can be scratched by a fingernail). Color: Tan, brown, or grayish. Luster: Pearly to vitreous. Crystal structure: Monoclinic. Cleavage: Perfect in one direction.

Hardness: 2 on Mohs scale (can be scratched by a fingernail)
Color: Tan, brown, or grayish
Luster: Pearly to vitreous

Identified July 16, 2026More mineral →

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Physical properties

Hardness: 2 on Mohs scale (can be scratched by a fingernail). Color: Tan, brown, or grayish. Luster: Pearly to vitreous. Crystal structure: Monoclinic. Cleavage: Perfect in one direction.

Formation & geological history

Evaporite mineral formed by the evaporation of seawater or saline lake water in arid basins. Often found in sedimentary environments such as salt flats and clay beds.

Uses & applications

Primary source of plaster of paris, drywall, and fertilizer. Also used as a soil conditioner and by collectors for unique crystal habits.

Geological facts

Gypsum is one of the most common minerals in sedimentary environments; it can form massive beds and is soft enough to be carved into intricate sculptures (alabaster).

Field identification & locations

Identified by its extreme softness and characteristic monoclinic crystal forms. Found globally in arid regions like the Sahara, US Southwest, and Mexico.