Azurite & Malachite specimens

13 pieces in the collection.

Chemistry

copper carbonates: azurite Cu₃(CO₃)₂(OH)₂ and malachite Cu₂CO₃(OH)₂

Crystal system

monoclinic

Mohs hardness

3.5 to 4

The two often form together; blue azurite slowly alters to green malachite. Soft, so dust them rather than washing.