Chalcopyrite (from the Greek. Χαλκóς «copper" + pyrite) also use a copper pyrites - a mineral with formula CuFeS2, crystallizes in the tetragonal crystal system.
Large crystals are rare and have a curved outer surface. Facets are usually covered with coarse hatching. Characteristic twinning, twins germination. It forms dense granular aggregates vkraplyuvannya, veins. Color butter yellow, honey-yellow, metallic sheen. Hardness 3.5-4. Cleavage is imperfect. In HNO3 dissolves with evolution of sulfur. Hydrothermal origin, in association with galena and sphalerite part of polymetallic ores. Formed as the processes termometamorfizmu. Important copper ore.The chalcopyrite is not found in solid solution with other sulphides. There is a limited replacement of copper with zinc, despite the chalcopyrite has similar structure to the sphalerite (the cell of the latter is the half along one of the dimensions of the cell; sphalerite cell has face-centered cubic).
However, presents contaminations of various kinds: Co, Ni, Mn, Zn and Sn replace the Cu and Fe. If, Fe and As replace sulfur; traces of Ag, Au, Pt, Pd, Pb, V, Cr, In, Al and Sb were found.
Probably many of these elements are present in microscopic mineral grown inside the crystal of chalcopyrite, for example lamellae of arsenopyrite or molybdenite, explain traces of Cu and Mo.