Zoisite
| Colour | Green, Blue, Pink |
|---|---|
| Mohs hardness | 6 to 7 |
| Lustre | Vitreous, pearly on cleavage surfaces |
| Streak | White or colorless |
| Crystal system | Orthorhombic |
| Transparency | Transparent to translucent |
| Cleavage | Perfect {010} imperfect {100} |
| Fracture | Uneven to conchoidal |
| Chemical formula | Ca 2 Al 3 (SiO 4 )(Si 2 O 7 )O(OH) |
| Specific gravity | 3.10–3.36 |
What is Zoisite?
Zoisite, first known as saualpite, after its type locality, is a calcium aluminum hydroxy sorosilicate. Its chemical formula is Ca2Al3(SiO4)(Si2O7)O(OH). It was formerly considered a member of the epidote group.
How to identify Zoisite
- Lustre: Vitreous, pearly on cleavage surfaces.
- Hardness: Mohs 6 to 7 — about as hard as a steel knife.
- Streak: White or colorless.
- Habit: Orthorhombic crystal system.
Zoisite in different forms
Stones often confused with Zoisite
Frequently asked questions
How hard is Zoisite?
Zoisite is Mohs 6 to 7 on the hardness scale.
What colour is Zoisite?
Zoisite is typically green, blue, pink (White, gray, greenish brown, greenish gray, pink, blue, purple).