Sodalite
| Colour | Blue, Green, Yellow, Purple |
|---|---|
| Mohs hardness | 5.5–6 |
| Lustre | Dull vitreous to greasy |
| Streak | White |
| Crystal system | Cubic |
| Transparency | Transparent to translucent |
| Cleavage | Poor on {110} |
| Fracture | Conchoidal to uneven |
| Specific gravity | 2.27–2.33 |
What is Sodalite?
Sodalite is a tectosilicate mineral with the formula Na8(Al6Si6O24)Cl2, with royal blue varieties widely used as an ornamental gemstone. Although massive sodalite samples are opaque, crystals are usually transparent to translucent. Sodalite is a member of the sodalite group with hauyne, nosean, lazurite and tugtupite.
How to identify Sodalite
- Lustre: Dull vitreous to greasy.
- Hardness: Mohs 5.5–6 — about as hard as a steel knife.
- Streak: White.
- Habit: Cubic crystal system.
Sodalite in different forms
Stones often confused with Sodalite
Frequently asked questions
How hard is Sodalite?
Sodalite is Mohs 5.5–6 on the hardness scale.
What colour is Sodalite?
Sodalite is typically blue, green, yellow, purple (Rich royal blue, green, yellow, violet, white veining common).