mineral

Satin Spar Gypsum (Satin Spar Selenite)

Gypsum (Calcium Sulfate Dihydrate - CaSO4·2H2O)

AI-generated identification · may be incorrect

Hardness: 2 on Mohs scale (can be scratched with a fingernail). Color: White, pearly, fibrous translucent structure. Luster: Silky to pearly. Crystal System: Monoclinic with parallel fibrous growth.

Hardness: 2 on Mohs scale (can be scratched with a fingernail)
Color: White, pearly, fibrous translucent structure
Luster: Silky to pearly

Identified July 24, 2026More mineral →

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Physical properties

Hardness: 2 on Mohs scale (can be scratched with a fingernail). Color: White, pearly, fibrous translucent structure. Luster: Silky to pearly. Crystal System: Monoclinic with parallel fibrous growth.

Formation & geological history

Formed as an evaporite mineral in ancient marine basins and salt lakes through the evaporation of saline waters.

Uses & applications

Widely carved into decorative items, candle holders, and towers; used commercially in drywall, plaster of Paris, and soil conditioner.

Geological facts

Trade-named 'Selenite' in the metaphysical industry, though true selenite refers to transparent, tabular gypsum crystals. Satin spar displays fiber-optic properties, conducting light along its parallel fibers.

Field identification & locations

Easily identified by its extreme softness (scratched by a fingernail), silky luster, and distinct parallel fibrous cleavage. Very soft and water-soluble over time.