Electrolytic refining is a process used to purify metals by means of an electrolytic cell. The process involves passing an electric current through a solution containing the impure metal as the anode and a pure metal as the cathode. The impurities dissolve into the electrolyte, while the pure metal is deposited on the cathode. The impure electrolyte leaving the anodes is removed from the cell and purified by removing iron, copper, etc., before being returned to the cell. Electrolytic refining is used to separate one metal in pure form from an alloy containing a high percentage of the desired metal, such as copper, and a number of other metals dissolved in the copper or intimately mixed with it. The process is also used to recover precious metals and by-product metals.