Copper Futures Rises on Supply Concern as BHP Mine Workers Extend Strike

Jul. 30 (Bloomberg) –Copper futures rebounded after a strike at Chile's Escondida mine, the world's largest source of the metal, stretched into an eighth day, signaling shrinking global supplies.

Union leaders at BHP Billiton Ltd.'s Escondida unit rejected an improved bonus offer by the company and vowed to continue the strike that has halted shipments from the mine. Escondida accounts for about a fifth of all copper produced in Chile, the world's top supplier.

"The market wants to rally," Adam Klopfenstein, a senior strategist at Lind-Waldock, a broker in Chicago, said in a telephone interview. "Investors make a scramble for the metal every time there is a big strike."

Copper futures for September delivery rose 1 cent, or 0.2 percent, to close at $4.4795 a pound at 1:12 p.m. on the Comex in New York. In July, the metal gained 4.6 percent, the most this year.

Earlier, the price fell as much as 1.3 percent amid signs of a sluggish U.S. economy and the political stalemate on the debt ceiling. The metal climbed 1.6 percent this week.

Futures may advance next week on supply concerns, a Bloomberg survey showed. Copper has gained 36 percent in the past year, reaching a record $4.6575 on Feb. 15, as mining companies struggled to keep pace with rising consumption.

On the London Metal Exchange, copper for delivery in three months rose $16, or 0.2 percent, to $9,830 a ton ($4.46 a pound).

Nickel also gained in London. Aluminum, lead, tin and zinc fell.