Azurite

**Chemical composition:** Cu₃(CO₃)₂(OH)₂

**Hardness:** 3.5

**Density:** 3.8 g/cm³

**Crystal system:** Monoclinic

**Luster:** ​​Vitreous

**Info:** Dark blue azurite is one of the two basic copper (II) carbonate minerals, the other being bright green malachite. Azurite was used as a blue pigment since antiquity, occasionally as beads in jewellery or as ornamental stones, and also as an a good surface indicator of the presence of weathered copper sulphide ores.

## Keywords
mineral azurite texture color ornamental stone semi-precious gemstone