Leucite
| Colour | White, Gray |
|---|---|
| Mohs hardness | 5.5–6 |
| Lustre | Vitreous |
| Streak | White |
| Crystal system | Tetragonal |
| Transparency | Transparent to translucent |
| Cleavage | Poor on {110} |
| Fracture | Conchoidal |
| Chemical formula | KAlSi 2 O 6 |
| Specific gravity | 2.45–2.50 |
What is Leucite?
Leucite (from the Greek word leukos meaning white) is a rock-forming mineral of the feldspathoid group, silica-undersaturated and composed of potassium and aluminium tectosilicate KAlSi2O6. Crystals have the form of cubic icositetrahedra but, as first observed by Sir David Brewster in 1821, they are not optically isotropic, and are therefore pseudo-cubic. Goniometric measurements made by Gerhard vom Rath in 1873 led him to refer the crystals to the tetragonal system. Optical investigations have since proved the crystals to be still more complex in character, and to consist of several orthorhom
How to identify Leucite
- Lustre: Vitreous.
- Hardness: Mohs 5.5–6 — about as hard as a steel knife.
- Streak: White.
- Habit: Tetragonal crystal system.
Leucite in different forms
Stones often confused with Leucite
Frequently asked questions
How hard is Leucite?
Leucite is Mohs 5.5–6 on the hardness scale.
What colour is Leucite?
Leucite is typically white, gray (White to grey).