Abstract: A process for treatment of zinc sulfide or other zinc bearing feed materials in conjunction with an iron sulfide containing mineral or compound to effect a separation of zinc from iron by fuming on either zinc and sulphur vapor or zinc sulphide vapor. The vapor is stripped and transported by a carrier gas from the mineral or a molten matte formed from the mineral. The process is operated at a temperature in the region of 1250.degree. to 1400.degree. C. and at a partial pressure of oxygen in the region of 10-.sup.7 to 10-.sup.11 bar. The process is conducted in the presence of a liquid matte phase which contains at least iron sulphide and which is intimately mixed in a bath with a slag phase.