Zinc is another mineral that is mined a lot. Zinc processing is the extraction of zinc from its ores and the preparation of zinc metal or chemical compounds for use in various products. The separation of metallic zinc from its ores by pyrometallurgy is much more difficult than with other common metals, such as copper, lead, and iron, because the reduction of zinc oxide by carbon (C) proceeds spontaneously only above the zinc boiling point of 907 °C (1,665 °F).

Its most important use, as a protective coating for iron known as galvanizing, derives from two of its outstanding characteristics: it is highly resistant to corrosion, and, in contact with iron, it provides sacrificial protection by corroding in place of the iron.

Most zinc mines produce zinc and lead or zinc and nickel. Some mines produce primarily zinc, but some mines produce zinc as a side-product of some metal that has a higher concentration in the ore. The world’s biggest mine is located in Rajasthan. Zinc is mined from underground. Hygiene and pollution pose special problems in both processes. At both plants extreme care has to be taken to work within existing hygiene standards. The main waste produced by the blast furnace-furnace slag-is stable and can be dumped safely without affecting surface water.