Lapis Lazuli Facts
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Lapis Lazuli Facts
| Chemical Composition | It is a rock composed of Lazurite (Na,CA)8(AlSiO4)6(SO4,S,Cl)2 , Hauynite (Na,CA)4-8(AlSiO4)6(SO4)1-2 , Sodalite Na8(AlSiO4)6Cl2 , Noselite Na8(AlSiO4)6SO4 , Calcite CaCO3 and Pyrite FeS2. |
| Colours | Intense deep blue with pyrite inclusions. Sometimes white coloured calcite lines also present. Other possible colour shades – purplish blue, greenish blue. |
| Hardness | Varies between 5-6 ( Mohs) . |
| Refractive Index | Approximately 1.50 |
| Specific Gravity | It varies between 2.7 to 2.9 and increases with the increase of pyrite content. |
| Luster | Greasy. |
| Solid State | Opaque |
| Crystal System | None as it is a rock. |
| Pleochroism | None |
| Phenomena | None |
| Fractures | Uneven |
| Enhancement | Frequently enhanced to improve the colour and durability by dying and impregnated. |
| Source | Afghanistan, Chile, Siberia, United States, Burma, Canada, Russia, Italy, Mongolia and Pakistan. |
| Precautions | Protect from sunlight, large temperature changes, cosmetics, harsh household cleaning products. |