16.46: Lapis Lazuli
- Page ID
- 4733
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| Lapis Lazuli | |
|---|---|
| Chemical composition | rock consisting of lazurite, hauyne, calcite and pyrite |
| Habit | aggregate |
| Fracture | uneven |
| Hardness | 5.5 |
| Refractive index | 1.500 - 1.670 |
| Specific gravity | 2.50 - 3.00 |
| Lustre | resinous to vitreous |
Figure \(\PageIndex{1}\): Lapis Lazuli with Pyrite inclusions
Enhancements
Common enhancements to lapis lazuli:
- Fracture filling - wax (with dye or without) - conceal cracks and fractures and to improve luster
- Dye - color staining - to produce evenly colored material
Images
Figure \(\PageIndex{2}\): Untreated lapis lazuli cabochon from Afghanistan.
Image courtesy of Scott Davies.