Gemdle

Benitoite

blue

Benitoite, a blue mineral
Géry PARENT · Public domain
ColourBlue
Mohs hardness6–6.5
LustreVitreous
StreakWhite
Crystal systemHexagonal
TransparencyTransparent to translucent
Cleavage[101] poor
FractureConchoidal
Chemical formulaBaTiSi 3 O 9
Specific gravity3.65

What is Benitoite?

Benitoite is a rare, blue, barium titanium cyclosilicate mineral, found in hydrothermally altered serpentinite. It forms in low-temperature, high-pressure environments typical of subduction zones at convergent plate boundaries. Benitoite fluoresces under short-wave ultraviolet light, appearing bright blue to bluish white in color. The more rarely seen clear to white benitoite crystals fluoresce red under long-wave UV light.

How to identify Benitoite

Can you spot Benitoite?

Test yourself on photos of Benitoite and lookalikes:

Frequently asked questions

How hard is Benitoite?
Benitoite is Mohs 6–6.5 on the hardness scale.
What colour is Benitoite?
Benitoite is typically blue (Blue, colorless).