Vesuvianite
Mineral Ca10(Mg,Fe)2Al4(SiO4)5(Si2O7)2(OH,F)4
Also called Idocrase, Californite, and Cyprine
About it
Square prisms in olive green to brown, formed where limestone meets intrusions; Quebec's Jeffrey mine gives purple and green crystals. First described from Vesuvius.
- Type
- Mineral
- Group
- Silicate (sorosilicate), vesuvianite group
- Formula
- Ca10(Mg,Fe)2Al4(SiO4)5(Si2O7)2(OH,F)4
- Hardness (Mohs)
- 6–7
- Specific gravity
- 3.33–3.45
- Streak
- white
- Lustre
- vitreous (glassy), resinous
- Crystal system
- Tetragonal
- Colours
- green, brown, yellow, purple, blue, pink
- Transparency
- transparent, translucent, opaque
- Cleavage and fracture
- poor; uneven fracture
Typical values: real specimens vary. For more, see mindat.org.