Wet semi-autogenous mills of MMPS type are designed for grinding of ferrous and non-ferrous metal ores, as well as gold containing ores. MMPS type mills are generally used at the first stage of grinding in two-stage operation mode. Use of large mills allows preliminary crushing stage exclusion. Ball mills of MSh type are designed for grinding of ferrous and non-ferrous metal ores as well as gold-containing ores. MSh type mills are generally used at the first stage of grinding in two-stage operation mode.