Chalkopyrit

Chalkopyrit, also known as chalcopyrite (CuFeS2), is a copper iron sulfide mineral and the most important copper ore worldwide. It is widely mined in many countries, and the name chalcopyrite derives from the Greek chalkos, meaning copper, and pyrites, reflecting its copper content and association with pyrite.

Chalkopyrit crystallizes in the tetragonal system and commonly forms fine to coarse crystals such as tetrahedra or dodecahedra. It has a metallic luster and a characteristic brassy yellow color that tarnishes to iridescent purples, blues, and greens. On the Mohs scale its hardness is 3.5 to 4, and it leaves a greenish-black streak with poor cleavage. The mineral has a specific gravity around 4.1 to 4.3.

Geologically, chalkopyrit forms in a variety of settings, most notably hydrothermal veins and porphyry copper deposits, and it also occurs in contact metamorphic zones and skarns. It is commonly associated with quartz, bornite, sphalerite, galena, and pyrite, and may occur as disseminations within igneous rocks or as fracture-filling crystals.

As the primary copper ore, chalkopyrit is concentrated by flotation and then smelted and refined to produce copper metal. It is a globally significant mineral for copper production, with major mining regions including Chile, Peru, the United States, Australia, and Indonesia.