metamorphic
Lapis Lazuli
Lazurite-rich metamorphic rock (approx. (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)
Hardness: 5-5.5 (Mohs scale), Color: Intense deep blue (often with gold pyrite or white calcite flecks), Luster: Vitreous to greasy, Crystal structure: Isometric (dodecahedral habits), Specific Gravity: 2.7-2.9
- Hardness
- 5-5
Identified More metamorphic →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 5-5.5 (Mohs scale), Color: Intense deep blue (often with gold pyrite or white calcite flecks), Luster: Vitreous to greasy, Crystal structure: Isometric (dodecahedral habits), Specific Gravity: 2.7-2.9
Formation & geological history
Formed via contact metamorphism of limestone or marble. The primary blue color comes from lazurite, formed in high-temperature environments. Most famous deposits are found in the Sar-e-Sang mines in Afghanistan which have been worked for over 6,000 years.
Uses & applications
Used primarily in jewelry, cabochons, and ornamental carvings. Historically crushed into powder for the pigment 'ultramarine' used in Renaissance paintings. Collectible for its deep pigment and pyrite inclusions.
Geological facts
Lapis lazuli was highly prized by the ancient Egyptians and was used in the funeral mask of Tutankhamun. It is technically a rock, not a mineral, because it is composed of several different minerals (lazurite, pyrite, and calcite).
Field identification & locations
Look for the signature 'royal blue' color with characteristic 'fools gold' (pyrite) inclusions. It will not scratch glass easily due to its moderate hardness. Commonly found in Afghanistan, Chile, Russia, and Canada.
More like this
