Prices mostly eased in Tuesday's London Metal Exchange (LME) pre-market trading, with light selling in Asia washing through to Europe, traders said.
Initially, the market rose in Asia after steady gains in London on Monday. But Shanghai copper futures closed sharply lower amid talk that China might allow the yuan to appreciate, which could lead to a surge in copper imports.
"The market was wrong-footed by a sharp sell-off at the tail end of Chinese business," a London trader said.
"We saw pockets of liquidation, and while there has been some trade support on the dips, the market is still seeing some selling.
"The market is a bit difficult to predict but a move towards $2,580/2,600 in copper might prove tricky this morning, although we think it could trend higher later in the day," he said.
LME stocks fell by 4,975 tonnes to a total of 336,225 tonnes.
Standard Bank London analyst Robin Bhar noted in his daily report that the speculative net long position on Comex had remained surprisingly stable - testimony perhaps to solid fundamentals and a belief there is more upside.
Three months copper was quoted at $2,564/568 a tonne by 1015 GMT, down $14 from Monday's kerb.
Aluminium was up $2 at $1,675/678 amid two-way business, with producer buying and scrap tightness aiding the firmer trend, traders and analysts said.
Angus MacMillan of Prudential Bache said the market would need to close above $1,675/80 to target $1,700, and diverging short-term moving averages suggested more upside.
Nickel was steady at $15,200/300, up $50, after a postponement to labour discussions at Canada's Falconbridge Sudbury works.
"Technically, prices have closed above the 30-day moving average at $15,154 and a close above $15,800 will signal a test of the upper end of the range at $16,550," Bhar said.
Other metals were slightly softer.
Lead shed $4 to $828/830, zinc eased $6 to $1,071/073, while tin lost $50 to $6,490/530.