metamorphic
Lapis Lazuli
Lazurite (primary mineral component), (Na,Ca)8(AlSiO4)6(S,SO4,Cl)1-2
Hardness: 5-5.5 on Mohs scale; Color: Deep celestial blue to midnight blue; Luster: Vitreous to greasy; Crystal structure: Isometric (dodecahedral); Cleavage: Poor/indistinct; Specific gravity: 2.7-2.9
- Hardness
- 5-5
- Color
- Deep celestial blue to midnight blue
- Luster
- Vitreous to greasy
Identified More metamorphic →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 5-5.5 on Mohs scale; Color: Deep celestial blue to midnight blue; Luster: Vitreous to greasy; Crystal structure: Isometric (dodecahedral); Cleavage: Poor/indistinct; Specific gravity: 2.7-2.9
Formation & geological history
Formed via contact metamorphism when limestone or marble is altered by hydrothermal activity. Major deposits date back millions of years, notably from the Sar-e-Sang mines in Afghanistan, which have been active for over 6,000 years.
Uses & applications
Primarily used for high-end jewelry, beads, cabochons, and carvings. Historically ground into pigment (ultramarine) for Renaissance paintings and cosmetics.
Geological facts
Lapis lazuli was highly prized by Ancient Egyptians, who used it in the funeral mask of Tutankhamun. It is actually a rock composed of multiple minerals: lazurite (blue), calcite (white veins), and pyrite (gold flecks).
Field identification & locations
Identify in the field by its intense blue color, the presence of golden brassy pyrite inclusions, and white calcite streaks. It is found most famously in Afghanistan, but also Chile, Russia, and Canada. Collectors look for a deep, uniform blue with minimal white calcite.
More like this
