mineral

Likely gypsum (selenite/alabaster)

Gypsum, CaSO₄·2H₂O

AI-generated identification · may be incorrect

White to colorless, nonmetallic and commonly pearly; often forms tabular or fibrous crystals. Mohs hardness 2; three cleavage directions, with one notably perfect; specific gravity about 2.3.

Identified October 8, 2026More mineral →

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Physical properties

White to colorless, nonmetallic and commonly pearly; often forms tabular or fibrous crystals. Mohs hardness 2; three cleavage directions, with one notably perfect; specific gravity about 2.3.

Formation & geological history

Forms when calcium-sulfate-rich water evaporates in sedimentary basins, or through hydration of anhydrite. Gypsum deposits occur across many geological ages; the photo alone cannot establish the specimen’s age or exact identity.

Uses & applications

Used to make plaster, drywall, and cement; clear selenite and carved alabaster are collected or used decoratively.

Geological facts

Gypsum is soft enough to scratch with a fingernail and can be scratched with a copper coin.

Field identification & locations

The pale, layered-looking piece is consistent with gypsum, but visual identification is uncertain; verify softness and cleavage, or use a hardness test. Common deposits include evaporite basins worldwide.