mineral

Moonstone

Orthoclase (KAlSi3O8) with Albite (NaAlSi3O8)

Hardness: 6.0-6.5 on Mohs scale. Color: Colorless to white/pearly with blue or white schiller. Luster: Vitreous to pearly. Crystal structure: Monoclinic. Cleavage: Perfect in two directions. Specific gravity: 2.56-2.59.

Hardness: 6
Color: Colorless to white/pearly with blue or white schiller
Luster: Vitreous to pearly

Identified July 6, 2026More mineral →

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Physical properties

Formation & geological history

Formed in igneous or metamorphic environments when feldspar minerals cool and separate into alternating layers of orthoclase and albite. This layered structure causes the characteristic adularescence (glow).

Uses & applications

Primarily used in jewelry as cabochons, beads, and carvings. Also highly valued by gemstone collectors and for metaphysical purposes.

Geological facts

The optical phenomenon called adularescence creates a billowy light that appears to float across the surface. Moonstone is the birthstone for June and is the state gem of Florida (commemorating the Moon landings).

Field identification & locations

Identified in the field by its pearly luster and distinctive adularescent glow when rotated under light. Commonly found in Sri Lanka, India, Myanmar, and Madagascar. Look for the 'blue flash' in higher quality specimens.

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Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

Schist

Metamorphic

Epidote

Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)

metamorphic

Gypsum (variety Selenite or Alabaster)

Calcium sulfate dihydrate (CaSO4·2H2O)

Mineral

Nephrite Jade

Nephrite

Mineral/Rock

Granite

Granite (Phaneritic intrusive igneous rock)

igneous