Metallurgy Refining, Alloying, Smelting | Britannica
Metallurgy Refining, Alloying, Smelting: Refining is the final procedure for removing (and often recovering as byproducts) the last small amounts of impurities left after the major extraction steps have been completed. It leaves the major metallic element in a practically pure state for commercial application. The procedure is accomplished in three ways: refining by fire, by electrolytic ...