The production of copper involves four main steps: mining, concentrating, smelting, and refining. At each step the purity of metal is increased through different physical and chemical processes.

Mining of copper ores takes place via open-pits for deposits located near the surface or via underground shafts for more difficult to reach deposits. The primary copper ore is Chalcopyrite, CuFeS2. Chalcopyrite is typically only 1-1.5% copper by weight and often contains other minerals such as gold, silver, and zinc.

Concentrating copper ore requires three steps: crushing, grinding and flotation. First the ore is crushed in a series of cone crushers. Then it is mixed with water and ground by a series of rod and ball mills. By this point the ore has been reduced to a finely ground slurry.

The slurry is mixed with chemicals and pumped into flotation cells which are shaken mechanically. This produces air bubbles which carry the copper minerals to the surface where they are collected. The unwanted residue or gangue sinks to the bottom of the flotation cells. Copper concentrate is typically 25-30% copper by weight. It also contains both harmful elements such as arsenic and mercury as well as desirable metals such as gold, silver, and zinc.

The concentrate is then shipped to smelters for further processing. There is an active market in copper concentrate that pits mines on the one side and custom smelters on the other. The price of copper concentrate is a combination of the finished metal prices minus treatment and refining charges.

The feedstock for copper smelters is copper concentrate. The concentrate is fed into flash furnaces that reduce it to matte containing 45-70% copper. The matte, along with flux and copper scrap, is then run through a converter which renders copper blister of 99% purity.

The final stage of the production process is the refining of copper blister into copper cathodes. First the blister is run though a refining furnace and cast into anodes. Then the anodes are electrorefined leaving cathodes of 99.95-99.99% purity.

Copper cathodes of minimum 99.95% purity are traded over the LME, COMEX, and SHFE.

Applications
According to the Copper Development Association, engineering and electrical applications for copper account for 41% of global consumption. Building construction accounts for another 48% of copper consumption.

Copper wiring is found in most buildings. Plumbing (copper tubes) and roofing also depend on copper. Most electronics contain copper as do computer chips and circuit boards. Copper also has important applications in the transport sector. According to the CDA, cars contain up to one mile of copper wires while airliners contain over one-hundred.

Given these broad applications copper is often described as the base metal with a PhD in economics. The demand for copper is tied to the economic growth of nations as they build out their infrastructure.