The pyrite tailings, containing about 0.2% of copper, 0.2% of zinc, about 0.7-1.5 g/t of gold and about 5-15 g/t of silver, are produced in the beneficiation cycle of non-ferrous sulfide ores. More than 80 million tons of these wastes have been accumulated. The gold and silver are associated with pyrite FeS₂. It is advisable to apply the technology of underground leaching without the use of sodium cyanide.