Copper futures in New York rallied at the open on Friday then extended gains after the July US employment report showed softer-than-expected jobs growth and suggested the Federal Reserve may not raise interest rates at its August meeting, traders said.
"We rallied in the face of an increase in both LME and Shanghai stocks. That would ordinarily be a negative. But in the face of this morning's employment data and the interest rate implications, the weak dollar, the firmer equity market, and of course Escondida, (are) all contributing to firmer trade here," said James Quinn, commodity commentator at AG Edwards.
Copper for September delivery was up 13.25 cents or 3.8 percent at $3.3620 per lb on the New York Mercantile Exchange's COMEX division. It advanced to nearly a three-week high at $3.6850 per lb.
Spot August added 14.05 cents or 3.98 percent to trade at $3.67 a lb, after charging up to a high at $3.72. COMEX estimated 10:00 am EDT volume at 5,000 lots.