Copper prices tumbled to a five-week low Thursday on expectations that
falling demand from China and a slowdown in the U.S. housing market will lead to
a surplus of the metal.
Other commodities traded mixed, with crude oil rebounding slightly and gold,
silver and soybeans falling. Corn and wheat futures rose.
China, the world's biggest buyer of copper, has been importing less of the
metal since the completion of most major construction projects heading into the
Beijing summer Olympics. Copper imports in June fell 20 percent compared to May,
China's custom's agency said this month. As a result, stockpiles of the metal
have swelled in Shanghai and London, helping drive down prices.