Zinc concentrate is the result of a flotation process after the zinc ore has been mined and milled. Zinc concentrate is an intermediate product used as raw material in the production of zinc metal. The quality of different zinc concentrate can vary but zinc sulphide concentrate is the most common one and it typically contain 45-55 percent zinc and 30 percent sulphur. Besides zinc and sulphur they generally also contain iron, lead and other impurities. Some zinc concentrates also contain precious metals.