Copper stockpiles held in duty-free warehouses in China, the top user, may be re-exported after surging to as much as 350,000 tons from almost none at the start of the year, according to Xi'an Maike Metal International Group. "We can hardly find buyers for refined copper," said Luo Shengzhang, general manager of the copper department at Xi'an Maike. The company ranks among the country's three biggest importers, according to the executive. "China's got to export some copper from now and next year," Luo said in an interview.