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Zinc comes from natural mineral deposits of ore in the earth s crust. The deposits may be close to the surface, in which case they will be mined from an open pit. Alternatively, they may be some distance underground and cannot be mined directly from the surface.
The Romans produced considerable quantities of brass (an alloy of zinc and copper) as early as 200 BC by a cementation process where copper was reacted with zinc oxide. The zinc oxide is thought to have been produced by heating zinc ore in a shaft furnace.