Minerals azurite, Cu3

Copper is obtained from ores containing the following minerals azurite, Cu3(C03)2(0H)2 chalcocite, CU2S chalcopyrite, CuFeS2 covelite, CuS cuprite, CU2O and malachite, Cu2C03(0H)2. Which mineral has the lowest copper content as a percent by mass ... 

Copper occurs in nature as native copper that is, in the free state. Other ores of copper include cuprite, CugO chalcocite, CugS clialcopyrite, CuFeSg malachite, Cu2C03(0H)2 and azurite, Cu3(C03)2(OH)2. Malachite, a beautiful green mineral, is sometimes polished and used in jewelry. 

Other economically important carbonate containing minerals include dolomite [CaMgCCOj) ], smithsonite (ZnCOj), both of which are white, and two important ores of copper—malachite [CUjCOjCOH) ], which is green, and azurite [Cu3(0H)2(C03)2], which is dark blue. 

Many of the minerals in the Earth s crust are not simple ionic compounds consisting of one type of cation such as Cu and one type of anion such as carbonate, COs ". These more complex compounds can be classified as double (or triple or quadruple) salts. (These salts are also referred to as ternary or quaternary.) That is, they contain more than one type of cation and/or more than one type of anion. For example, one of the conunon ores of copper is malachite, which has the formula Cu2C03(0H)2. This is an ionic compound that contains the Cu " ion and both the carbonate and hydroxide anions. Double salts can be thought of as combinations (but not mixtmes) of two or more simple salts. Malachite can be visualized as CuCOs -1- Cu(OH)2. Malachite is frequently found with azurite, which has the formula Cu3(C03)2(0H)2. Azurite simply has a different ratio of the two simple salts 2 CuCOs + Cu(OH)2. 

Azurite is a bright blue hydrated copper carbonate mineral of composition Cu3(C03)2(0H)2. Isomorphous with the green mineral malachite (. v.), the isostructural synthetic analogue. 

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