mineral

Vesuvianite (Idocrase)

Ca19(Al, Mg, Fe)13(SiO4)10(Si2O7)4(OH, F, O)10

AI-generated identification · may be incorrect

Hardness: 6.5; Color: Olive green to brown or white (massive); Luster: Vitreous to resinous; Crystal structure: Tetragonal; Cleavage: Poor; Specific gravity: 3.32-3.47

Hardness: 6
Color: Olive green to brown or white (massive)
Luster: Vitreous to resinous

Identified March 4, 2026More mineral →

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Physical properties

Hardness: 6.5; Color: Olive green to brown or white (massive); Luster: Vitreous to resinous; Crystal structure: Tetragonal; Cleavage: Poor; Specific gravity: 3.32-3.47

Formation & geological history

Forms primarily in contact metamorphic environments within skarn deposits and metamorphosed limestones at the contact area of silicate magmas.

Uses & applications

Mainly a collector's mineral; transparent crystals are sometimes cut into gemstones for jewelry. It is also an important indicator mineral for geological mapping of skarn zones.

Geological facts

Also known as Idocrase, it was first discovered on Mount Vesuvius in Italy, giving it its common name. The name Idocrase comes from the Greek 'eidos' (form) and 'krasis' (mixture).

Field identification & locations

Identify by its square cross-section in crystals, olive green color, and occurrence in calc-silicate rocks (skarns). Commonly found in Italy, Canada (Quebec), and the USA (California/Vermont).