4. Zinc and the environment

4.1 Zinc: a natural element

Zinc is naturally present in air, water and soil. Most rocks and many minerals contain zinc in varying proportions. The natural concentration of zinc in the earth's crust ranges from 10 to 300 mg/kg, with an average value of 70 mg/kg (dry matter).

In some places, zinc has been concentrated to much higher levels under the influence of geological and geochemical processes. Such concentrations, found on the Earth's surface and underground, are exploited in the form of ore mining. The most common zinc mineral is sphalerite (ZnS). Zinc metal is produced both from ores and from the recycling of zinc-containing products.

Around 30% of the world's zinc consumption today comes from recycled zinc.

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