The most-traded copper contract on the Shanghai Futures Exchange rose 3 percent to 47,160 yuan ($6,812) a tonne on Wednesday, gathering momentum on the back of a surge in Chinese producer prices in December. Zinc held its gains on the back of news that processing fees for China's zinc smelters hit record lows last month as supply from mines continued to dwindle. Shanghai zinc rose 1.7 percent. ShFE aluminium was up 2.7 percent. ShFE nickel was 1.13 percent firmer.
Underlying that is rising concerns of further supply-side disruptions. Workers at Chile's Escondida copper mine - the world's biggest - have already rejected a wage offer from BHP Billiton. Also, a proposed ban on the export of copper concentrates from Indonesia is due to come into force on January 12. "While the government is expected to issue new export rules later this week, traders appear nervous," ANZ commodities strategist Daniel Hynes said in a note.