mineral

Satin Spar Selenite

Gypsum (Calcium Sulfate Dihydrate, CaSO4·2H2O)

Hardness: 2 on Mohs scale (can be scratched by a fingernail); Color: Translucent white with a pearly or silky luster; Crystal Structure: Monoclinic; Cleavage: Perfect in one direction; Specific Gravity: 2.3

Hardness: 2 on Mohs scale (can be scratched by a fingernail)
Color: Translucent white with a pearly or silky luster

Identified March 4, 2026More mineral →

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Physical properties

Formation & geological history

Forms primarily as an evaporite mineral in sedimentary environments, such as prehistoric lake beds or evaporating seas, often through the precipitation of calcium-rich waters over hundreds of thousands of years.

Uses & applications

Commonly used in the production of plaster of Paris, drywall, and fertilizer. In the metaphysical community, it is popular as a cleansing stone and decorative carving material.

Geological facts

Satin spar is often confused with 'true' Selenite, which is the clear, plate-like form of gypsum. The name Selenite is derived from the Greek word 'selene' meaning 'moon' due to its soft white glow.

Field identification & locations

Identify by its fibrous appearance and extreme softness; it should be easily scratched by a fingernail. It is widely found in Morocco, Mexico, and across the southwestern United States. Keep away from water as it can dissolve or lose its luster over time.

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