Copper extends longest rally since December on China

Copper extends longest rally since December on China. Copper gained for a seventh session in New York, extending the longest rally in six months, as manufacturing growth in China bolstered demand prospects amid signs of tight supply. A preliminary Purchasing Managers' Index from HSBC Holdings Plc and Markit Economics rose to 50.8 in June, topping the 49.7 median estimate of analysts surveyed by Bloomberg. That was the first time this year the reading was above 50, signaling expansion. Inventories tracked by the main exchanges in London, Shanghai and New York fell for an eighth session to the lowest since October 2008. Copper futures for delivery in September advanced 0.9 percent to settle at $3.142 a pound at 1:12 p.m. on the Comex in New York, extending the longest rally since Dec. 16. Prices climbed to $3.1515, the highest since June 3.