Copper prices fell to eight-week lows on Wednesday as rising inventories in Asian warehouses fueled fears about weaker demand ahead in top consumer China.
A stronger dollar, eroding the purchasing power of commodity buyers outside the US, and slide in oil prices also pressured industrial metals prices.
Benchmark copper on the London Metal Exchange (LME) was down 1 percent at $4,664 a ton at 1445 GMT, its lowest since June 27.
Stocks of copper in LME-approved warehouses have risen by a quarter, more than 50,000 tons since Aug. 11, to 254,700 tons, with much of the build occurring in South Korea and Singapore.
“The huge inventory rise in Asian warehouses suggests China is exporting its surplus and we’ve some pretty strong copper export numbers,” said Societe Generale analyst Robin Bhar.
“A surge in mine supply in the first half of the year has translated into excess refined metal.
Exports of unwrought copper and copper products from China jumped to 75,022 tons in July, more than a fivefold rise from the same month last year and analysts interpreted it as a sign of weak local demand.
The rise in mine supply in the first half of the year came mostly from Peru, much of it ending up in China to be processed into refined metal by local smelters.
Chinese imports of copper ores and concentrates from Peru nearly doubled to more 2.43 million tons in the seven months to July.
“All that refined metal is leaving China because it can’t find a home,” one copper trader said, adding that activity was subdued ahead of a speech from Fed Chair Janet Yellen on Friday, which may yield clues to the timing of US rate interest rises.
Yellen is speaking at Kansas City Fed’s 2016 Economic Symposium in Jackson Hole from Thursday to Saturday.
“There is some confusion as to what the Fed will do. Some economic numbers have been stronger, so the latest thinking is perhaps they will move in September as opposed to December,” said INTL FCStone analyst Edward Meir.
In other metals, LME tin climbed 1 percent to $18,885, hitting an 18-month peak for the second day running on worries about shortages as inventories slide to their lowest since 2008.
“Charts look quite bullish and so we have raised our upside target to $19,100,” Meir said in a note.
Three-month aluminum fell 0.5 percent to $1,661 a ton while zinc dipped 0.2 percent to $2,297.50.
Lead gained 0.6 percent to $1,873 and nickel shed 0.4 percent at $10,215.

Source: Arab News