metamorphic

Blue Quartzite (Aventurine)

Silicon Dioxide (SiO2) with Dumortierite or Crocidolite inclusions

AI-generated identification · may be incorrect

Hardness: 7 (Mohs scale); Color: Blue to denim blue; Luster: Vitreous to waxy; Crystal Structure: Trigonal (microcrystalline); Cleavage: None; SG: 2.6-2.7

Hardness: 7 (Mohs scale)
Color: Blue to denim blue
Luster: Vitreous to waxy

Identified June 28, 2026More metamorphic →

Explore Blue Quartzite (Aventurine) in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness: 7 (Mohs scale); Color: Blue to denim blue; Luster: Vitreous to waxy; Crystal Structure: Trigonal (microcrystalline); Cleavage: None; SG: 2.6-2.7

Formation & geological history

Formed through the regional metamorphism of quartz-rich sandstone. The blue color typically comes from the presence of tiny inclusions of fibrous minerals like dumortierite during the recrystallization process.

Uses & applications

Commonly used for tumbled stones, decorative beads, cabochons for jewelry, and as ornamental garden stones.

Geological facts

Blue aventurine is often called a 'stone of self-discipline.' Unlike Lapis Lazuli, it lack brassy pyrite flecks, and unlike Sodalite, it is much harder and lacks white calcite veining.

Field identification & locations

Identify by its hardness (will scratch glass) and its grainy, sugary texture visible under a lens. Found frequently in Brazil, India, and parts of Russia.