Lapis Lazuli Facts

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.
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