In New York, the May COMEX contract gained 4.95 cents to settle at $3.8975 per lb on Thursday, near the upper end of its $3.8250 to $3.9030 session range. Volumes remained relatively light this week. Close to 52,000 lots traded in late New York business, more than a quarter below the 30-day norm, according to preliminary Thomson Reuters data.
Copper prices have seesawed between around $8,400 ($3.81) and $8,600 ($3.90) this week as investors weigh an overall improved outlook for global growth against disappointing copper demand in China, which consumes about 40 percent of global consumption. "The US is no longer the centre of gravity in the (copper) market, but if the US is recovering it gives you an awful lot of positive investor sentiment," said Natixis analyst Nic Brown.