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kernite - hydrated sodium borate, an uncommon borate mineral

$ 7.50

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kernite         Na2B4O6(OH)2 3H2O


Kernite, hydrated sodium borate, is used to produce borax, a closely related chemical compound to the mineral borax, differing in its crystal water content. This specimen is from the U.S. Borax Mine at Boron, Kern County, California. U.S. Borax is currently a part of Rio Tinto Minerals. This is the largest borax mine in the world and the world's largest source of kernite.  Initially called rasorite after Clarence M. Rasor of Pacific Coast Borax Co., kernite was renamed after the county. It is now also mined in Argentina and Turkey.

Near Boron, underground mining began in 1872, with colmanite and ulexite mined from clay beds roughly 100 feet below the surface. The U.S. Borax Mine was opened in 1923 - the discovery of kernite was made during the drilling of a water well in 1926. Mining is now open pit. This mine is the largest open pit mine in California

Kernite slowly dehydrates, forming a white film of tincalconite. This specimen is a cleavage prism.

Click here for an interesting video of the U.S. Borax operations at Boron.



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