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Exports to China jumped to 2,973 tonnes, up from 1,050 tonnes a year before, accounting for a quarter of Japan's total exports.
Zinc is mainly used as an anti-corrosive coating in galvanised steel production and in plating.
Japan's zinc smelters lost nearly 70 percent of their output capacity after the March 11 earthquake in 2011 due to damage to facilities, but production has since recovered. Taiwan and Indonesia are other key markets for Japanese zinc.