Abstract: An apparatus for use in extracting primary zinc metal from ore concentrates is described. The apparatus includes first and second electrolytic cells, the first cell receiving an acid zinc sulfate solution derived from an ore concentrate, and having an anode which is insoluble in said solution, and the second cell containing an alkaline electrolyte and having a cathode which is insoluble in said electrolyte. A common electrode is also provided which is insoluble both in the acid zinc sulfate solution and in the alkaline electrolyte. The common electrode can be transferred between the first cell, in which it acts as a cathode, and the second cell, in which it acts as an anode. The zinc sulfate solution is subjected to electrolysis in the first cell with the common electrode acting as a cathode, thereby causing primary zinc metal to be deposited as a coating on the common electrode.