Copper flat, aluminium at three-year high

Copper closed almost flat on Thursday after data showing that US first-quarter economic growth slowed more than expected and jobless claims rose offset the benefits of a sharply weaker dollar. Benchmark copper on the LME closed at $9,320 a tonne from a close of $9,321 on Wednesday. The metal used in power and construction is down more than 8 percent from February's record high of $10,190 a tonne.
"Copper is having a hard time being pushed about the place," said Danske Bank analyst Arne Lohmann Rasmussen. BHP Billiton is ploughing $554 million into boosting output at Chile's Escondida, the world's No. 1 copper mine, where output has dwindled in recent years due to declining ore grades.
Chile, which holds the world's top copper reserves and is the No.1 producer, is expected to steadily increase output in the next two years with new mine projects and upgrades, although its output fell 0.1 percent in March. Metals are expected to stay supported ahead of a long weekend in London, a trader said. The London Metal Exchange will be closed for a royal wedding on Friday and a bank holiday next Monday. "Is it going to be a marriage rally or a wedding slump? The market will be a bit unsure about what to do because tomorrow New York will be open, so I don't think we'll get much of a conclusion," said a London LME trader.
LME copper stocks rose by a small 150 tonnes to 463,650 tonnes, their highest since mid-June, the latest data showed. The inventories have climbed by a third since mid-December. "The steady rise in copper, zinc and lead inventories is a prime cause for concern," Commerzbank said in a note. LME zinc stocks have jumped by nearly 30,000 tonnes this month. Zinc closed at $2,247 from $2,240.
Aluminium was $2,767 a tonne, from a bid of $2,743.50. It earlier rallied 1 percent to $2,778.80 a tonne, its highest since August 2008 on prospects that rising power prices will push up input costs for the energy intensive metal. Nickel closed at $26,850 from $26,630, having tipped a two-week high at $27,000 earlier. Tin was $32,050 from a bid of $31,995 with a small drawdown from stockpiles in Rotterdam signalling some returning consumer demand. Battery material lead closed at $2,491 from $2,498.