Quiz: Remember the definition of mal de mer?
A dark-blue monoclinic mineral occurring as a mass of crystals (an aggregate) or in the form of blades with wedge-shaped tips. It is often found together with the mineral malachite in copper deposits. Azurite is used as a source of copper, as a gemstone, and as a dye for paints and fabrics. Chemical formula: Cu3(CO3)2(OH)2.
basic copper carbonate [Cu3(OH)2(CO3)2]. It is ordinarily found with malachite in the oxidized zone of copper lodes. Notable deposits are Tsumeb, Namibia; Chessy, Fr.; and Bisbee, Ariz., U.S. Azurite was used as a blue pigment in ancient Eastern wall painting and, from the 15th to the middle of the 17th century, in European painting. For detailed physical properties, see carbonate mineral (table)