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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.
Centuries before zinc was recognized as a distinct element, zinc ores were used for making brass (a mixture of copper and zinc). A brass dating from between 1400-1000 BC has been found in Palestine. An alloy containing 87% zinc was found in prehistoric ruins in Transylvania. The smelting of zinc ores with copper was apparently discovered in Cyprus and was used later by the Romans. Metallic zinc was produced in the 13th century in India by reducing calamine (zinc carbonate, ZnCO 3) with organic substances such as wool. The metal was rediscovered later in Europe.