Azurite and malachite microcrystals

This azurite from Kolwezi, DR Congo, shows a compact group of deep blue crystals, characteristic of this hydrated copper carbonate. The surface displays dense crystallisation, with marked relief and several areas where the mineral texture remains clearly visible.

Very fine malachite microcrystals appear in places on the surface of the azurite. This azurite-malachite association, typical of the copper deposits of Katanga, adds further mineralogical interest to the piece without altering the dominant blue colour of the specimen.

Collected in 2015, this 37 x 37 mm mineral belongs to the small-format specimens sought after for the quality of their crystallisation and for the interest of the association between two well-known copper carbonates: azurite, with the formula Cu3(CO3)2(OH)2, and malachite, with the formula Cu2CO3(OH)2.