* Euro falls to three-week low versus dollar * Euro zone manufacturing shrinks for 15th month in Oct * Coming up: U.S. non-farm payrolls for Oct at 1230 GMT By Harpreet Bhal LONDON, Nov 2 (Reuters) - Copper prices slipped on Friday, and were on course for their fourth weekly drop, as uncertainty about economic growth and the outlook for demand kept investors cautious ahead of the release of labour market data from the United States. Also weighing on metals prices was a jump in the dollar index to a seven-week high, while the euro slipped to a three-week low. A strong dollar makes commodities priced in the U.S. unit more expensive for holders of other currencies. Three-month copper on the London Metal Exchange slipped to $7,772.25 a tonne at 1008 GMT, down 0.7 percent from Thursday's close of $7,826 a tonne. Investors are awaiting U.S. nonfarm payrolls data at 1230 GMT, which is likely to provide fresh direction to prices. The U.S. unemployment rate probably rose in October as employers stepped up hiring only slightly, underscoring President Barack Obama's vulnerability in next week's presidential election. "There is still not much conviction out there and positioning is still pretty light across the metals," said Gayle Berry, analyst at Barclays Capital. "A lot of the flows have been dominated by the CTAs (commodity trading advisors) and what we are not seeing is the discretionary investors coming in and taking fundamentally driven views on the market because there are macro risks still out there." Data over the past month has shown the health of the global economy remains fragile, with retail sales and the housing market pointing to an improvement in the United States but Europe is still struggling. Latest data showed the euro zone manufacturing shrank for the 15th month running in October as output and new orders fell, a survey showed on Friday, likely fuelling expectations of further easing from the European Central Bank. CHINA EYED In China, the world's largest consumer of copper, concerns remained about the outlook for demand which has remained sluggish this year, but traders did not expect to see a big sell-off. "Overall, investors are bearish about copper due to weak physical demand in China, which many thought should have improved by now," said a Shanghai-based trader. "While we may see prices inch down gradually in the near term, I doubt we will see a deep plunge this year since the economic data out of China and the U.S. have been encouraging." Prices for the metal rallied nearly 8 percent in September, fuelled by the third round of quantitative easing (QE) by the U.S. Federal Reserve, the promise of bond buying by the European Central Bank (ECB) and stimulus measures in Japan and China. Copper weakened in October, ending more than 5 percent lower on the month, as expectations that real demand for metals would improve failed to materialise. In industry news, Japan Pan Pacific Copper sold 120,000 tonnes of copper to China under a 2013 term contract at $85 premium, sources said. In other metals, aluminium was at $1,944.75 a tonne from Thursday's close of $1,940. "Prices could see another $10-15 on the upside, but we would recommend selling into strength given the market's creaky fundamentals," ANZ said in a note. Lead was at $2,127 from $2,126.50, tin slipped to $22,300 from $20,375 while nickel fell to $16,263 from $16,350. Zinc was at $1,890.75 from Thursday's close of $1,889. Metal Prices at 1008 GMT Comex copper in cents/lb, LME prices in $/T and SHFE prices in yuan/T Metal Last Change Pct Move End 2011 Ytd Pct move COMEX Cu 352.65 -2.55 -0.72 344.75 2.29 LME Alum 1944.75 4.75 +0.24 2020.00 -3.73 LME Cu 7770.25 -55.75 -0.71 7600.00 2.24 LME Lead 2128.25 1.75 +0.08 2034.00 4.63 LME Nickel 16265.00 -85.00 -0.52 18650.00 -12.79 LME Tin 20230.00 -145.00 -0.71 19200.00 5.36 LME Zinc 1889.75 0.75 +0.04 1845.00 2.43 SHFE Alu 15360.00 25.00 +0.16 15845.00 -3.06 SHFE Cu* 56610.00 -460.00 -0.81 55360.00 2.26 SHFE Zin 14840.00 0.00 +0.00 14795.00 0.30 ** Benchmark month for COMEX copper * 3rd contract month for SHFE AL, CU and ZN SHFE ZN began trading on 26/3/07

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