mineral
Moonstone
Orthoclase Feldspar ((Na,K)AlSi3O8)
AI-generated identification · may be incorrectHardness: 6-6.5 (Mohs scale), Color: Colorless, white, pale yellow, pale blue, Luster: Vitreous to pearly, Crystal structure: Monoclinic, Cleavage: Perfect in two directions, Specific gravity: 2.56-2.59
- Hardness
- 6-6
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Physical properties
Hardness: 6-6.5 (Mohs scale), Color: Colorless, white, pale yellow, pale blue, Luster: Vitreous to pearly, Crystal structure: Monoclinic, Cleavage: Perfect in two directions, Specific gravity: 2.56-2.59
Formation & geological history
Formed in igneous and metamorphic rocks, often pegmatites. The adularescence is caused by light scattering between microscopic layers of orthoclase and albite.
Uses & applications
Commonly used in jewelry, cabochons, and as a collector's stone.
Geological facts
Moonstone exhibits a unique optical phenomenon called adularescence, a soft glow that appears to float just below the surface of the stone.
Field identification & locations
Identified by its characteristic adularescent glow. Found in Sri Lanka, India, Madagascar, Myanmar, and the USA. Collectors look for stones with a strong blue sheen.
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