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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.
Quick Answer. Silver is found embedded in several different minerals, namely copper, zinc and lead, and the refining process varies depending on the source. Silver derived from copper and its derivatives, including copper sulfide, requires different handling and refining techniques than silver minerals taken from zinc deposits and lead sources.