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Neptunite

Neptunite Value, Price, and Jewelry Information


An overview on Neptunite Jewelry and Gemstones. Covers details and essential information on the physical properties and characteristics of Neptunite gems.

HomeGemstonesNeptunite Value, Price, and Jewelry Information
By Joel E. Arem, Ph.D., FGA, updated on

Optics: a= 1.690-1.691; β=1.693-1.700; γ=1.719—1.736.

Biaxial (+)

Occurrence: In alkaline rocks and carbonatites but most especially embedded in natrolite in San Benito County, California, where it occurs in spectacular crystals associated with benitoite and joaquinite.

Narsarsuk, Julianhaab district, Greenland.

Mt. Ste. Hilaire, Quebec, Canada.

Kola Peninsula,USSR: mangan-neptunite.

San Benito County, California.

Name: For Neptune, god of the sea in mythology, because it was found associated with aegirine, named after Aegir, Scandinavian god of the sea.

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