Monday, 6 March 2017

Benitoite

Benitoite is a rare blue barium titanium silicate, found in hydrothermally altered serpentinite. It was first described in 1907 and named benitoite for its occurrence near the headwaters of the San Benito River in San Benito County, California. Benitoite occurs in a number of locations, but gemstone quality material has only been found in California. In 1985 benitoite was named as the official state gem of California.
Top quality Benitoite can be expensive. Rich blue, clean stones at carat and above sizes often command high prices. Clarity enhances value. Very light and very dark stones reside at the lower end of the value spectrum.

At the apex are medium-dark stones.
Although Benitoite is a valuable and exquisite gemstone, its hardness is relatively low (6-6.5 on the Mohs Scale) and it is prone to scratching. Large crystals of Benitoite are exceedingly rare, and they are usually preserved as mineral specimens. Benitoite gemstones are strongly fluorescent, and give off a bright blue color in shortwave ultraviolet light.