Kernite Locality: US Borax Mine—U.S. Borax and Chemical Corporation, Boron, California Original description: Kernite. Close view. Collected by Kenneth C. Bulloc — Photo: Andrew Silver · Public domain
Kernite
Also known as: Rasorite.
A hydrated sodium borate — the huge-crystaled 'rasorite' mined at Boron, California, an important boron ore.
Intro adapted from Wikipedia (CC BY-SA).
Kernite is an IMA-recognized mineral species in the borate class, with the chemical formula Na₂B₄O₆(OH)₂·3H₂O.
It crystallizes in the monoclinic crystal system (space group P2_1/c).
Key properties: Mohs hardness 2.5–3; specific gravity 1.906; typically white or colorless or gray; White streak; Vitreous, satiny on fibrous cleavages luster; refractive index 1.471; optically biaxial.
IMA symbol Ker, grandfathered status — known before the IMA’s founding, named in 1927.
An important ore mineral of borax in sedimentary borate deposits, deposited under warm conditions or formed by metamorphism.
It is found associated with Borax, inyoite, ulexite, colemanite.
The name refers to Kern Co., California, USA, in which Boron is located.
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