Benitoite can occur in rich blue crystals that are as striking and flawless as the finest sapphires. Gem quality benitoite is found only in a small area of San Benito County, California. It has never been found in quantity or as crystals much larger than 5 cm across. The scarcity of this beautiful gem makes it primarily a collector's item. However, a minor amount of high quality benitoite is used to help align and adjust electron microprobe beams.
Benitoite was discovered in 1906 by J.M. Couch at the now well-known Benitoite Gem Mine in San Benito County. The mineral was thought to be sapphire, but jewelers determined that it wasn't. In 1907, George D. Louderback, a mineralogy professor at the University of California identified it as a new mineral species, and named it benitoite after the river, county and nearby mountain range where it was found.
This stone weighs 2.69 carats.