"Metal companies that depend on a single metal cannot secure a sustainable competitive advantage," Lu said.

Chinalco has completed an US$860 million takeover of Peru Copper and plans to buy a 49 percent stake in Yunnan Copper Group.

Xiao Yaqing, Chinalco's president, said copper, which now accounts for less than 10 percent of its income, could become a major revenue earner for the company.

The acquisition of Peru Copper and Yunnan Copper would give Chinalco total copper reserves of about 20 million tons - more than Jiangxi Copper, the mainland's biggest producer.

Chinalco and British company Aricom, which owns a titanium mine in Russia, have also struck a deal to co-invest 2.2 billion yuan in a titanium project in Jiamusi, in Northeast China's Heilongjiang Province. The project will have an initial output of 15,000 tons and is expected to begin operation in 2009. Its output is expected to reach 30,000 tons after second-phase construction.

Chinalco's listed unit Chalco is publicly traded in Hong Kong, New York and Shanghai. Chinalco posted a first-half sales increase of 36.2 percent on Friday from a year earlier, and 10.8 percent net profit growth, buoyed by a series of takeovers that boosted capacity.

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