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SANTIAGO, June 30 (Reuters) - Chile, the world No. 1 copper producer, had output of 508,245 tonnes of the red metal in May from the year before, boosted by new projects and operational improvements at an unidentified "important" processing plant, government statistics agency INE said on Tuesday.
Copper production increased 2.1 percent from a year earlier, and was 7.8 percent higher than April 2015.
Chile, which produces one-third of the world's copper, is struggling with dwindling ore grades in many of its aging deposits, although new mines are helping to boost output.
Although INE did not specify which operations had contributed to the rise, state-owned Codelco's Ministro Hales, Polish miner KHGM's Sierra Gorda, and Japanese-owned Caserones have ramped up production over the last year and are likely responsible for the jump in output.
From January through May Chile produced 2.43 million tonnes of copper, up 2.3 percent from the same period a year earlier.
Production of molybdenum, a metal used to harden steel, surged 19.7 percent to 4,872 tonnes in May from the year earlier. (Reporting by Anthony Esposito; Editing by Chizu Nomiyama and Jeffrey Benkoe)