Glencore Plc led a global slump in mining shares on concern China’s decision to devalue the yuan will sap demand for commodities.

Glencore, the mining and commodities company led by billionaire Ivan Glasenberg, tumbled 7.7 percent to a record low as of 3:30 p.m. in London. BHP Billiton Ltd. and Alcoa Inc. slid at least 4 percent. Freeport-McMoRan Inc. plunged 12 percent the day after announcing plans to sell as much as $1 billion in shares.

China devalued the yuan as policy makers stepped up efforts to support exporters and boost the role of market pricing in Asia’s largest economy. The central bank cut its daily reference rate by 1.9 percent, triggering the yuan’s biggest one-day drop since China ended a dual-currency system in January 1994.

The devaluation raises the risk that exports from China will increase, adding more metal to markets that are already oversupplied. A weaker yuan may also make imports for Chinese businesses more expensive and cut demand for raw materials in the world’s biggest consumer of commodities.

“China may export more semi-finished product, which should put pressure on commodity prices, hurting guys like Glencore,” John Meyer, a mining analyst at SP Angel Corporate Finance LLP, said by phone from London.

All six main metals on the London Metal Exchange fell more than 2 percent, with zinc touching the lowest in two years. Aluminum dropped to a six-year low.

The Bloomberg World Mining Index of 79 producers declined 2.3 percent, set for the biggest drop in two weeks.

“China’s materials-intensive growth cycle is maturing,” said Tom Price, an analyst at Morgan Stanley in London. (source from Bloomberg News)

• [Editor:Juan]