Native state (metallurgy)

For other uses, see Native state.

Metals in their native state are those found in nature as free elements (chemically uncombined). They are usually attached to or mixed with varying amounts of undesired material (gangue), and require only physical separation to produce usable metal. Most metallic ores in the Earth's crust require chemical processing to produce metal. Oxides and sulfides require smelting. Bauxite, an ore of aluminium, requires electrolysis. Many metals are found in uncombined metallic form, in varying degrees of purity. These "metals found as metals" are referred to as native metals, which are a subset of native element minerals. The most well-known native metals are native copper and gold. Nonreactive noble metals usually occur in nature as native metals.