mineral

Satin Spar Selenite

Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O

Hardness: 2 (very soft, can be scratched by a fingernail). Color: White, pearly, or colorless. Luster: Pearly to silky (satin-like). Crystal Structure: Monoclinic, often fibrous. Cleavage: Perfect in one direction.

Hardness: 2 (very soft, can be scratched by a fingernail)
Color: White, pearly, or colorless
Luster: Pearly to silky (satin-like)

Identified June 8, 2026More mineral →

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Physical properties

Formation & geological history

Formed primarily as an evaporite mineral in sedimentary environments where seawater or saline groundwater evaporates. It can also form during the oxidation of sulfide ores or through volcanic activity.

Uses & applications

Used in plaster of Paris, drywall (gypsum board), soil conditioners, and as decorative carvings and meditation tools in the crystal healing community.

Geological facts

The name 'Selenite' comes from the Greek word 'selene', meaning moon, referring to its pale, moon-like glow. The Naica Crystal Cave in Mexico contains giant selenite crystals over 30 feet long.

Field identification & locations

Identified by its extreme softness (scratchable with a fingernail) and its fibrous, silky luster. Common in evaporated sea beds, deserts, and caves. Look for parallel fibrous bundles that reflect light.

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Arenite (SiO2 based)

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Schist

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Nephrite Jade

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Mineral/Rock

Banded Gneiss (River Rock/Pebble)

Gneiss (specifically a banded variety often found as a river rock)

Metamorphic Rock

Biotite Schist

Biotite-rich Schist [K(Mg,Fe)3AlSi3O10(F,OH)2]

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