Copper Carbonates

Copper Carbonates

 

carbonate salts of copper. Normal copper carbonate has not been isolated yet. Copper carbonate (basic) occurs in nature as the emerald green mineral malachite, CuCO3 · Cu(OH)2, and the sky blue mineral azurite, 2CuCOa. Cu(OH)2. The basic carbonate CuCO3 - Cu(OH)2 · 0.5H2O is obtained by the action of Na2CO3 on CuSO4 in an aqueous solution; upon heating, the carbonate is converted into malachite.

Copper carbonates are unstable and at temperatures above 200°C break down into CuO, CO2, and H2O. They are insoluble in water but can be dissolved in ammonia in the presence of ammonia salts. Azurite is used as a pigment; it is also used in pyrotechnics, metallurgy, and other industries. Both azurite and malachite are used in the fashioning of decorative objects and jewelry.

References in periodicals archive ?
bearing sulphides have weathered to copper carbonates and copper oxides,
Proposed work includes identification of a diverse suite of copper minerals (including copper carbonates, copper halides, copper sulfates and copper sulphides) using polished thin sections, followed by analysis using a " .
Mining extracted ferruginous silicified slate with copper carbonates (malachite and azurite) passing into cuprite, native copper and minor chalcocite in what appears to be a classic supergene profile.
After covering principles of corrosion, it explains oxides and hydroxides, copper carbonates, chlorides, sulphates, sulphides, phosphates & nitrates, silicates and salts.
Copper, with grades shown in Table 2, is mainly contained in chalcopyrite, bornite, chalcocite, and copper carbonates in the oxide zone.
Lindorfer reports a diverse suite of secondary copper minerals from the Property, including copper carbonates (azurite, malachite), copper halides (atacamite), copper sulphates (brochantite) and copper oxides (cuprite, tenorite).