The Noril'sk complex, in East Siberia, produced 70% of the country's copper, and planned to increase output of cuprous ore from its Oktyabr'skiy underground mine, from 100,000 tons per year to 1.6 million tons, because the cuprous ores were 40% higher in copper content than the nickel-rich ores; the Oktyabr'skiy mine supplied 70% of Noril'sk's ...Web