* Copper market watches stocks for price clues * Uncertainty about global growth drags on * Coming up: Fed's summary of economic conditions at 1800 GMT By Pratima Desai LONDON, Sept 7 (Reuters) - Copper prices rose on Wednesday as labour disputes at mines threatened supplies and the dollar slipped, but nervousness about demand from top consumers China and the United States curbed gains. Benchmark copper on the London Metal Exchange traded at $9,099.75 a tonne by 1400 GMT, from $8,933 a tonne at the close on Tuesday. Supporting the metal used in power and construction was the commencement of a two-day strike by workers in Peru's third-biggest copper mine Cerro Verde, controlled by Freeport McMoran , with further threats of an indefinite walkout later this month according to union leaders. Adding to the supply worries, Freeport's Indonesia mine workers are set to strike from Sept. 15 to Oct. 15 unless the firm meets their demands for a pay rise. A weak dollar also underpinned metals prices, with the dollar falling 0.4 percent against a basket of currencies. A lower U.S. currency makes commodities priced in dollars cheaper for holders of other currencies. But analysts expect gains to be kept in check in the short-term by lingering uncertainty about the trajectory of global economic growth which could hamper demand for industrial metals. "Things will remain pretty choppy and prices are likely to trade sideways over the next few weeks due to the fact that the European banking crisis is showing no real signs of going away and global PMI(purchasing managers index) numbers are still going south," said Daniel Smith, head of metals research at Standard Chartered. Data from earlier this week showed disappointing services PMI figures from China, India, Britain and the euro zone, raising fears that the world's economy is facing another recession. Alongside equities and bonds, metal markets are watching the euro zone debt crisis and looking for clues to the health of the U.S. economy, the world's largest, and growth prospects in China. "Uncertainty is likely to remain high and the slowdown in the economy may drag on for an extended period," Credit Suisse Private Banking said in a note. China accounts for nearly 40 percent of global copper demand estimated this year at around 19 million tonnes. The United States accounts for about 10 percent of global consumption. FEW SIGNS OF PICK-UP Stocks of copper in LME approved warehouses stand at 465,250 tonnes, little changed in recent months. Cancelled warrants -- material earmarked for delivery -- at a mere 1.26 percent of total stocks also show few signs of a pick up in demand. "Copper inventories rose in the early part of the year, till about May, since then there hasn't been much change. I think prices are still too high for the Chinese," a copper trader said. "They are waiting to see what happens." Three-month aluminium traded at 2,397.50 a tonne from $2,380 a tonne on Tuesday, zinc traded at $2,237.25 from $2,190, lead at $2,426.75 from $2,388. Tin rose to $24,299 a tonne from $23,875. Nickel traded at $21,301 a tonne from $20,675. Metal Prices at 1400 GMT Comex copper in cents/lb, LME prices in $/T and SHFE prices in yuan/T Metal Last Change Pct Move End 2010 Ytd Pct move COMEX Cu 409.80 5.30 +1.31 444.70 -7.85 LME Alum 2389.50 9.50 +0.40 2470.00 -3.26 LME Cu 8990.50 57.50 +0.64 9600.00 -6.35 LME Lead 0.00 -2388.00 -100.00 2550.00 -100.00 LME Nickel 21220.00 545.00 +2.64 24750.00 -14.26 LME Tin 24090.00 215.00 +0.90 26900.00 -10.45 LME Zinc 2214.00 24.00 +1.10 2454.00 -9.78 SHFE Alu 17425.00 130.00 +0.75 16840.00 3.47 SHFE Cu* 67800.00 800.00 +1.19 71850.00 -5.64 SHFE Zin 17145.00 290.00 +1.72 19475.00 -11.96 ** 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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