Metallurgy

Metallurgy, the science and technology of extracting metals from ores, the methods of refining, purifying, and preparing them for use, and the study of the structure and physical properties of metals and alloys. A few unreactive metals such as silver and gold are found native (uncombined), but most metals occur naturally as minerals (i.e., in chemical combination with nonmetallic elements). Hydrometallurgy uses chemical reactions in aqueous solutions to extract metal from ore. Electrometallurgy uses electricity for firing a furnace or electrolytically reducing a metallic compound to a metal. Pyrometallurgy covers roasting, smelting, and other high temperature chemical reactions.