Chalcopyrite (CuFeS₂) is the most important copper ore, accounting for the majority of global copper reserves. Mining involves open-pit or underground extraction, followed by flotation to concentrate chalcopyrite, then smelting and electrorefining to produce pure copper. Chalcopyrite is also a source of sulfur dioxide for acid production. Copper production centers — Chile, Peru, China, the U.S., and the DRC — dominate chalcopyrite mining. Production volumes track global copper demand for electrical wiring, construction, and renewable energy infrastructure. Technological advancements in flotation and hydrometallurgical leaching have improved recovery rates, though chalcopyrite’s refractory nature makes low-grade ore processing challenging.