* Copper stocks up again, highlighting still weak demand

* Aluminum stocks surge nearly 36,000 tonnes

* Dollar rebounds, equities fall, weighing on metals

Copper prices ended lower on Thursday, pulling back from 14-month highs amid a recovery in the dollar from recent lows and as concerns grew that prices are running ahead of weak fundamentals.

Copper for December delivery on the New York Mercantile Exchange's COMEX division fell 2.95 cents to close at $3.0810 a lb, backing away from Wednesday's session peak at $3.1720, its highest level since late September 2008.

On the London Metal Exchange (LME), benchmark copper ended at $6,790 a tonne, down $90 from the close on Wednesday, when the metal used in power and construction hit a peak of $6,992 -- another high dating back to late September 2008.

"We've moved up a tremendous amount in the last three days," said Justin Lennon, an analyst at Mitsui Bussan Commodities in New York. "It's all this sideline money that wants to get into commodities."

"Copper inventories are increasing. Prices can get ahead of themselves ... commodities are a little bit in uncharted waters, making it very volatile," he added. "We're expecting some weakness in December but it's possible that we could get through the $7,000-level before the end of the year."

Mixed economic data in the United States and an analyst downgrade of the semiconductor sector industry weighed on the broader market and added to a growing anxiety over the economic outlook, traders said.

The Conference Board said its index of leading economic indicators climbed less than expected in November, while the Philadelphia Federal Reserve Bank said its business activity index rose to a two-year high in November.

"I think there is just a lot of renewed anxiety out there now," said Matthew Zeman, head of trading with LaSalle Futures Group in Chicago. "The chip sector was downgraded today ... technology is really the leader, so once again people are wondering if these markets have overshot where the economy is in real time."

Highlighting the poor fundamental backdrop, latest LME data showed copper stocks rose 6,450 tonnes to total 420,550, their highest since late April. Shanghai copper stocks are at their highest in five-and-a-half years.

Additional weight was seen from the dollar, which rose against a basket of currencies, making dollar-priced metals more expensive for non-U.S. investors.

Copper prices have risen more than 120 percent this year, benefiting from dollar weakness, Chinese buying, new investor cash and improving economic data.

Limiting copper's downside was news that BHP Billiton halted all operations at its Spence copper mine in Chile after striking workers invaded the installations.

Also, workers at Chile's massive Chuquicamata mine asked state copper giant Codelco for a 7.5 percent salary hike in contract talks that could set a tough precedent for the world's top producer.

ALUMINUM STOCKS SURGE

Among other metals, aluminum, used to make vehicles and packaging, ended at $2,031 a tonne from $2,065 with latest LME data showing stocks surged 35,925 tonnes to total 4.595 million tonnes, near record levels.

LME aluminum stocks have risen sharply this week, with a lot of the deliveries going into warehouses in Detroit indicating demand from the auto sector was weakening.

But Citigroup analyst David Thurtell said the market overlooked bearish stocks data as a lot of aluminum was tied up in financing deals and not available for consumption, while options activity added support.

On Wednesday, aluminum hit $2,095 a tonne, its highest since early August.

Zinc closed at $2,215 from $2,248, while stainless steel-making ingredient nickel, the worst performing metal in recent weeks, ended at $16,975 from $17,200.

LME zinc stocks are at four-year highs, while nickel stocks are at 15-year highs, as demand from the stainless steel sector remains weak.

Battery material lead closed at $2,332 from $2,403, while tin ended at $14,860 from $15,195.