Copper fell on Friday after Chinese growth data came below expectations, deepening worries over slower demand from the world's top metals consumer; while a stronger dollar and concerns about the euro zone debt crisis also undermined the metal.
Three-month copper traded at $8,120 in official rings, down more than 1 percent from a close of $8,220 on Thursday. Earlier it hit a session low of $8,008.75, its lowest in almost three months.
The red metal used in power and construction was on course for a 3 percent fall this week.
China's economy grew at its slowest in nearly three years in the first three months of 2012, with a weaker than expected reading that raised investor concerns that a five-quarter long slide has not bottomed and that more policy action will be needed to halt it.
China's Q1 GDP was lower than expected as well as Q1 home sales, adding to recently negative sentiment and renewed growth fears, VTB Capital analyst Andrey Kryuchenkov said.
Anyhow, growth of over 8 percent is not that bad, just lower than expected. This will push the government to increase public spending. The focus is back on China at the moment, but really people should worry more about Europe.
Italian three-year borrowing costs rose by more than a full percentage point at an auction on Thursday, boosted by fresh concerns about weaker euro zone states.
Spain's debt situation was also in focus. Madrid's borrowing costs rose at an auction last week as investors fretted about its ability to meet budget deficit goals.
Capping losses was the hope that the Chinese government will step up its growth policies and inject more liquidity in the system to prevent a further slowdown. Market players were also cheered by better-than-expected data in areas such as March industrial output and first-quarter fixed asset investment.
The Chinese data is certainly not catastrophic. On the contrary, it confirms the soft landing argument, said metals consultancy T-commodity in a research note.
However it does underline that the dragon economy remains at the moment in stand-by before a rebound forecast in the second half of the year.
The euro eased against the dollar after the Chinese data disappointed traders positioning for a strong showing. A stronger U.S. currency makes dollar-priced commodities such as metals costlier for holders of other currencies.
Doubts over buying from Chinese copper end-users are the main concern for investors at the moment.
Copper demand in China has picked up slightly since the beginning of April as consumers came back to restock a little. But overall, demand remains weak and stocks are still too high, said a Shanghai-based trader.
Copper stocks in warehouses monitored by the Shanghai Futures Exchange have quadrupled since the beginning of the year.
China's demand for refined copper may revive only by September as current heavy stockpiles are depleted and Beijing takes steps to boost the cooling economy, analysts and sources at copper products manufacturing plants said on Thursday.
Tin traded at $22,650 from a $22,655 close on Thursday.
Supporting tin prices, Indonesia finance minister said the country will issue a mining export tax regulation by June, showing the government is pushing ahead with a policy that is worrying resource firms.
Zinc, used to galvanize steel exchanged hands at $2,013 from $2,040 Thursday's close.
Battery material lead traded at $2,075 from $2,098 and aluminum at $2,089 from $2,104.
Nickel, untraded in rings was bid at $18,455 from $18,800.