gemstone

Moonstone

Orthoclase (KAlSi3O8) or Oligoclase with adularescence

Hardness: 6-6.5 Mohs; Color: Colorless to white/bluish; Luster: Vitreous to pearly; Crystal structure: Monoclinic; Features adularescence (a blue or white pearly sheen).

Hardness: 6-6
Color: Colorless to white/bluish
Luster: Vitreous to pearly

Identified July 19, 2026More gemstone →

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Physical properties

Hardness: 6-6.5 Mohs; Color: Colorless to white/bluish; Luster: Vitreous to pearly; Crystal structure: Monoclinic; Features adularescence (a blue or white pearly sheen).

Formation & geological history

Formed in igneous and metamorphic rocks, specifically pegmatites, as cooling magma allows intergrowth of orthoclase and albite layers.

Uses & applications

Primarily used in jewelry as cabochons, earrings, or rings; also used as a birthstone and for spiritual/metaphysical collection.

Geological facts

The unique glow, called adularescence, is caused by light scattering between microscopic layers of different feldspar minerals. It was incredibly popular during the Art Nouveau period.

Field identification & locations

Identify by its characteristic 'milky' or 'blueish' glow that moves across the surface as the stone is turned. It is commonly found in Sri Lanka, India, and Madagascar.

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Diamond and Gold Jewelry

Carbon (Diamond) / Au (Gold)

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Ammolite

Ammolite (Biogenic Aragonite with trace elements; fossils of Placenticeras meeki and Placenticeras intercalare)

mineral

Cubic Zirconia (simulant) or Diamond

ZrO2 (Cubic Zirconia) or C (Diamond)

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Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

sedimentary

Cubic Zirconia (or possibly Diamond)

Zirconium dioxide (or Carbon)

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Faceted Gemstone

Unknown transparent mineral, possibly Diamond (C), Cubic Zirconia (ZrO2), Quartz (SiO2), or Glass

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