metamorphic
Lapis Lazuli
Na6Ca2(Al6Si6O24)(SO4,S,Cl,OH)2 (Lazurite-dominated rock)
Hardness: 5-5.5 (Mohs scale), Color: Deep royal blue often with gold pyrite flecks, Luster: Vitreous to dull, Crystal structure: Isometric (as lazurite crystals), Cleavage: Imperfect/Poor, 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: Deep royal blue often with gold pyrite flecks, Luster: Vitreous to dull, Crystal structure: Isometric (as lazurite crystals), Cleavage: Imperfect/Poor, Specific Gravity: 2.7-2.9
Formation & geological history
Formed through contact metamorphism where heat and chemical changes occur in limestone or marble. Major deposits formed during various geological ages, notably in the Hindu Kush mountains of Afghanistan for over 6,000 years.
Uses & applications
Primarily used as a gemstone for jewelry (cabochons, beads), decorative carvings, and historically ground into the pigment 'ultramarine' for fine art paints.
Geological facts
Renowned as one of the oldest traded gemstones; it was a favorite of Ancient Egyptian pharaohs (used in Tutankhamun's funeral mask) and was the most expensive pigment in the Renaissance, used by artists like Michelangelo.
Field identification & locations
Identify by its intense 'lapis blue' color that does not scratch easily with a copper penny but will be scratched by steel. Often found in Afghanistan, Chile, and Russia. Collectors look for uniform blue without white calcite patches.
More like this
