Judging quality
Vesuvianite is often mistaken for epidote or green tourmaline; its square cross-section and blunt pyramidal termination settle it. The massive green Californian variety is sold as californite and imitates jade.
Silicate
Vesuvianite
Also called idocrase. Stubby tetragonal prisms in bottle green to olive, with a resinous lustre; the Jeffrey Mine in Quebec produced the finest gem crystals ever found before it closed.
Care
Reasonably hard. Water and cloth; no acids.
History & lore
Described from the lavas of Vesuvius in 1795, one of the first minerals named from a volcanic setting.
Cultural history, recorded as tradition rather than as medical or scientific claim.
Common questions about Vesuvianite
- What is Vesuvianite?
- Also called idocrase. Stubby tetragonal prisms in bottle green to olive, with a resinous lustre; the Jeffrey Mine in Quebec produced the finest gem crystals ever found before it closed.
- How hard is Vesuvianite and what is it made of?
- Vesuvianite is a Silicate-family mineral with the composition Ca10(Mg,Fe)2Al4(SiO4)5(Si2O7)2(OH)4. It crystallizes in the tetragonal system and rates 6-7 on the Mohs hardness scale. It occurs in green, olive green, brown, yellow-green.
- Where does Vesuvianite come from?
- Notable localities for Vesuvianite include Mount Vesuvius, Italy, Quebec, Canada (Jeffrey Mine), Pakistan, California, USA.
- How do you tell good Vesuvianite from filler?
- Vesuvianite is often mistaken for epidote or green tourmaline; its square cross-section and blunt pyramidal termination settle it. The massive green Californian variety is sold as californite and imitates jade.
- How do you care for Vesuvianite?
- Reasonably hard. Water and cloth; no acids.
See it in person
Photographs only go so far
Both rooms are open six days a week, and there is always someone happy to pull pieces out of the case so you can compare them under the light.