Benitoite is a rare blue barium titanium cyclosilicate, found in hydro-thermally altered serpentinite.

It forms in low temperature, high pressure environments typical of subduction zones at convergent plate boundaries and can occur in rich blue crystals that are as striking and flawless as the finest sapphires.

Gem quality is found only in a small area of San Benito County, California.

Why is it blue? The most distinctive feature is its blue color, which is caused by the presence of trace amounts of manganese.

Under a shortwave ultraviolet (UV) light, the gem glows a bright blue to bluish white. That is the chief way “rock hounds,” or collectors, can identify it. The mineral can be visually identified by its glassy, blue color and double triangle shape.
The more rarely seen clear to white benitoite crystals fluoresce red/pink under long-wave UV light.

It is so expensive because of its rarity. There is only one commercial mine in California, and its unique qualities come from its combination of barium, titanium, and silica.

The Crystal Collector, Bryan Major and nephew Dylan Ross set out to dig for rare California State Gemstone Benitoite crystals in Coalinga, California! This location is open to the public and a great spot for people of all ages!

This makes it highly valued, sometimes even more than Diamonds, Sapphire, Ruby, Emerald, or Tanzanite. Good quality gems regularly sell for over $5,000 a carat and some go for double that rate.

USES

Collector’s item
Benitoite is a rare gemstone that’s sought after by collectors and gem enthusiasts. It’s especially valued for its intense blue color, brilliance, and unique crystals.

Electron microprobe beams
A small amount of high quality benitoite is used to help adjust and align electron microprobe beams.

MOHS HARDNESS

6 to 6.5

LUSTER

Vitreous

CHEMICAL COMPOUND

BaTiSi₃O₉

WHERE TO FIND

It is found in very few locations including San Benito County, California, Japan and Arkansas. In the San Benito occurrence, it is found in natrolite veins within glaucophane schist within a serpentinite body.

DIAGNOSTIC PROPERTIES

Tabular dipyramidal crystals. Intense blue fluorescence under short-wave ultraviolet light. Associated with serpentine and albite, but more importantly with rare minerals such as natrolite, joaquinite, and neptunite.