![]() | This article includes a list of general references, but it lacks sufficient corresponding inline citations. (November 2008) |
In metallurgy, refining consists of purifying an impure metal. It is to be distinguished from other processes such as smelting and calcining in that those two involve a chemical change to the raw material, whereas in refining the final material is chemically identical to the raw material. Refining thus increases the purity of the raw material via processing.[clarification needed] There are many processes including pyrometallurgical and hydrometallurgical techniques.