Zoisite
Mineral Ca2Al3(SiO4)(Si2O7)O(OH)
Also called Anyolite
About it
The orthorhombic twin of clinozoisite; best known as blue-violet tanzanite from Merelani, Tanzania, green anyolite with ruby, and pink thulite from Norway.
- Type
- Mineral
- Group
- Silicate (sorosilicate), epidote group
- Formula
- Ca2Al3(SiO4)(Si2O7)O(OH)
- Hardness (Mohs)
- 6–7
- Specific gravity
- 3.15–3.36
- Streak
- white
- Lustre
- vitreous (glassy), pearly
- Crystal system
- Orthorhombic
- Colours
- blue, violet, green, grey, brown, pink, white
- Transparency
- transparent, translucent, opaque
- Cleavage and fracture
- perfect in one direction
Typical values: real specimens vary. For more, see mindat.org.