mineral

Satin Spar Gypsum (Satin Spar Selenite)

Hydrous calcium sulfate (CaSO4%C2%A02H2O)

Hardness: 2 on the Mohs scale (can be scratched with a fingernail). Color: White, translucent to silky pearly sheen. Luster: Silky to pearly. Crystal Structure: Monoclinic, forms fibrous parallel aggregates.

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

Identified July 24, 2026More mineral →

Explore Satin Spar Gypsum (Satin Spar Selenite) in the encyclopedia →

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Physical properties

Formation & geological history

Formed as an evaporite mineral in saline lake beds or shallow sea basins where seawater rich in calcium and sulfate evaporates over time.

Uses & applications

Used widely for ornamental carvings, polished wands, metaphysical items, and in industry for manufacturing drywall, plaster of Paris, and soil conditioner.

Geological facts

Although commonly sold in metaphysical shops as 'Selenite', it is technically the fibrous variety of gypsum known as Satin Spar. True selenite forms clear, flat, transparent sheets.

Field identification & locations

Easily identified by its extreme softness (scratched by fingernails) and distinct fibrous texture that exhibits a cat's-eye (chatoyant) light effect along its length. Common sources include Morocco, Mexico, USA, and Madagascar.

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Metamorphic

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Potassium Feldspar (Orthoclase)

Orthoclase (KAlSi3O8)

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Gypsum (variety Selenite or Alabaster)

Calcium sulfate dihydrate (CaSO4·2H2O)

Mineral

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Nephrite

Mineral/Rock