chalcopyriet

Chalcopyrite, with the chemical formula CuFeS2, is a copper iron sulfide mineral and the most important copper ore in the world. The name derives from Greek chalcos, meaning copper, and pyrite, meaning stone.

In appearance, chalcopyrite has a metallic luster and a brass-yellow color that ages to iridescent tarnish showing purples, blues, and greens. It typically forms in the tetragonal crystal system and can occur as well-formed crystals but is more often found as massive, granular aggregates. The mineral has a hardness of about 3.5 to 4 on the Mohs scale and a specific gravity around 4.1 to 4.3. It has little to no true cleavage and tends to fracture unevenly.

Chemically, chalcopyrite contains roughly 34.5% copper by weight, with iron and sulfur making up the remainder. It is a relatively common sulfide mineral in a variety of ore deposits and can display slight compositional variation, though its defining formula remains CuFeS2.

Chalcopyrite forms mainly in hydrothermal veins, porphyry copper deposits, and other sulfide-bearing geologic environments where copper-rich fluids precipitate with iron and sulfur. It is commonly associated with minerals such as pyrite, sphalerite, galena, bornite, and quartz. Near the surface, chalcopyrite can oxidize to secondary copper minerals such as malachite and azurite.

Economically, chalcopyrite is the primary source of refined copper worldwide. Ore processing involves crushing, grinding, and beneficiation to concentrate the mineral, followed by smelting and refining to produce copper metal and its downstream products.