* Copper down 1.7 pct on LME, down 0.1 pct on ShFE * Speculators shorting copper -trader * China Sept copper imports up 11.8 pct on month * Coming Up: U.S. initial jobless claims; 1230 GMT (Updates prices, adds quotes and details) By Carrie Ho SHANGHAI, Oct 13 (Reuters) - London copper slipped 1.7 percent on Thursday on lingering worries over the euro zone crisis and uncertainties ahead of key Chinese data this week also weighing on base metals. Three-month copper on the London Metal Exchange fell to $7,403.25 a tonne by 0703 GMT, after touching $7,544.75 in the previous session, its highest since Sept. 28, before closing 3.2 percent higher. LME copper has risen 7.2 percent from the start of the month until Wednesday's close, after losing a quarter of its value in the three months through Sept. 30. The most-active December copper contract on the Shanghai Futures Exchange SCFc3 closed 0.1 percent lower at 54,880 yuan ($8,630.966) per tonne. Despite a pick-up in copper buying for immediate use by Chinese consumers in recent weeks, speculators are selling based on fears of a gloomy global economic climate. "Speculators, both overseas and in China, are more inclined to short base metals today, especially copper, as the price of the metal is still far above its marginal costs, which means there is more downside room in a bear market," said a Shanghai-based trader. Analysts put copper's current marginal costs at $4,000. A Chinese industry group has told copper experts the country's stocks reached a surprisingly high 1.9 million tonnes at the end of last year, the Financial Times reported on Wednesday, citing unnamed sources. The source for the figures, the China Non Ferrous Metals Industry Association, has since confirmed those stockpile numbers to Reuters. But analysts said this would not dampen copper's outlook. "The figures are not surprising to me, since the import numbers were quite low earlier this year, and all signs point to the fact that China had been drawing down from this high stockpile for most of the year. I believe that we have only 40 percent of those stocks left," Jinrui Futures analyst Zhao Kai said. Data showed that China's imports of copper rose 11.8 percent to 380,526 tonnes to a 16-month high in September from the previous month. Analysts said this was due to favourable arbitrage and spot premiums, as well as steady prices in August, which encouraged forward orders for delivery in September. The euro zone's debt crisis continues to weigh on sentiment despite efforts to straighten out the region's finances and recent positive news. The bloc is set to ask banks to accept losses of up to half on their holdings of Greek debt as part of a plan to avert a disorderly default and stem a crisis that threatens the world economy. Euro zone industrial production was much stronger than expected in August, data showed on Wednesday, indicating the economic slowdown in the third quarter might be smaller than feared. Italy is set to pay lower yields when it sells up to 6.5 billion euros of bonds on Thursday, with growing optimism that European leaders are responding more effectively to the euro zone debt crisis outweighing two rating downgrades in less than a week. In industry news, Chile's state copper giant Codelco said on Wednesday it secured a $6.75 billion bridging loan from Japan's Mitsui & Co, enabling it to exercise an option to buy a 49 percent stake in Anglo American Sur. Base metals prices at 0703 GMT Metal Last Change Pct Move YTD pct chg LME Cu 7403.25 -125.75 -1.67 -22.88 SHFE CU FUT DEC1 54880 -50 -0.09 -23.62 LME Alum 2236.50 -11.50 -0.51 -9.45 SHFE AL FUT DEC1 16660 -85 -0.51 -1.07 HG COPPER DEC1 334.60 -4.75 -1.40 -24.63 LME Zinc 1939.00 -6.00 -0.31 -20.99 SHFE ZN FUT DEC1 15160 -45 -0.30 -22.16 LME Nickel 18950.00 -130.00 -0.68 -23.43 LME Lead 2036.00 -34.00 -1.64 -20.16 SHFE PB FUT 14910 10 +0.07 -18.75 LME Tin 22541.00 -459.00 -2.00 -16.20 LME/Shanghai arb 350 Shanghai and COMEX contracts show most active months ^ LME 3-m copper in yuan, including 17 pct VAT, minus SHFE third month

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