Azurite, Cu3(CO3)2(OH) (Basic Copper Carbonate), is so named because of its intense blue colour, which also explains its popularity with collectors. The colour is very distinctive, although the shade varies among specimens. It is formed by the action of carbon dioxide and water on copper sulfides.

Description: A good quality specimen of Azurite consisting of a fused clusters of blade-like crystals. These are largely triclinic and overlap in many places. The colour is very deep blue, especially in strong light, which also gives rise to many strong reflections. Otherwise the depth of colour appears almost black. Some of the thinner crystals are semi-transparent producing a startling blue transmitted light.

Location: Anif Migrane Mine, Morocco.