Production of refined copper rose 12.1% to 120,576 tonnes in the first four months of this year, while refined gold output advanced 12.3% to 7.6 tonnes. The central bank is purchasing all of the gold refined in Kazakhstan.
Production of crude steel plunged by 22.0% to 1.06 million tonnes.
Kazakhmys and ENRC, as well as Glencore-controlled Kazzinc, account for a large part of Kazakhstan's metals production. ArcelorMittal owns the country's only major steel plant.
The steel plant in Temirtau faced a sudden shock to demand in 2012 when Western financial sanctions on Iran closed the door on a market that accounted for a considerable portion of its sales last year.