metamorphic
Lapis lazuli
Lazurite-bearing calcite marble; typically lazurite (Na₃CaSi₃Al₃O₁₂S), calcite, pyrite
AI-generated identification · may be incorrectBlue, opaque, with white calcite and possible brassy pyrite flecks; Mohs hardness 3–5.5, generally dull to waxy luster, granular texture, no prominent cleavage, specific gravity about 2.7–2.9.
Identified More metamorphic →
Explore Lapis lazuli in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Blue, opaque, with white calcite and possible brassy pyrite flecks; Mohs hardness 3–5.5, generally dull to waxy luster, granular texture, no prominent cleavage, specific gravity about 2.7–2.9.
Formation & geological history
Formed when limestone or marble was metamorphosed and altered by sulfur-rich fluids, commonly during mountain building; specimens may be hundreds of millions of years old. The blue color comes mainly from lazurite.
Uses & applications
Used as a decorative stone, beads, cabochons, carvings, and historically as the ultramarine pigment. These appear to be small rough or partially polished pieces.
Geological facts
The strongest blue material is traditionally sourced from Badakhshan, Afghanistan, a famous deposit worked for over 6,000 years. White calcite lowers grade, while visible pyrite can increase appeal.
Field identification & locations
Common sources include Afghanistan, Chile, Russia, and Pakistan; identify it by intense royal-blue color, white calcite veining, and occasional pyrite, while avoiding confusion with dyed howlite or sodalite. Acid may fizz on calcite, but testing can damage the specimen.
More like this
