Copper mining

Copper has the symbol Cu and the atomic number 29. It is a ductile and malleable metal with high electrical and thermal conductivity. It belongs to the element group of transition metals. Copper is one of the few metals to naturally occur as an uncompounded mineral. Copper is a metal that reacts with oxygen slowly to form a layer of copper oxide on copper metal. However, in contrast to the oxidation of iron by wet air that the layer formed by the reaction of air with copper has a protective effect against further corrosion.
A number of countries, such as Chile and the United States, still have sizable reserves of the metal which are extracted through large open pit mines, though high demand relative to supply has caused a price spike in the 2000s. In 2005, Chile was the top mine producer of copper with at least one-third world share followed by the USA, Indonesia and Peru.

To mine copper, the first step is to blast the copper ore from a open pit mine, then loaded and transported to the primary crushers. Then the ore is crushed and screened, with the fine sulfide ore going to froth flotation cells for recovery of copper. The coarser ore goes to the heap leach, where the copper is subjected to a dilute sulfuric acid solution to dissolve the copper. Then the leach solution containing the dissolved copper goes through solvent extraction. This process concentrates and purifies the copper leach solution. The concentrated copper solution is dissolved in sulphuric acid and sent to the electrolytic cells for recovery as copper plates (cathodes). From the copper cathodes, it is manufactured into wire or appliances.