Gold trading was mixed on Thursday ahead of the release of key US data, which may offer clues as to whether the US Federal Reserve will cut interest rates next year and determine the metal's direction.

Trading was thin ahead of the year-end holidays, making gold prone to sharp fluctuations. Trading range was seen at $610 to $650 until the end of the year, according to some dealers.

"With fund managers looking to balance their accounts, do some window dressing before the end of the year, there is the potential for a few wobbles in things like the US dollar and the oil price," said a dealer in Sydney.

"That should be reflected in the gold price as well," he said.

Spot gold hit a bid high of $621.30 ounce, still down slightly from $621.70/623.20 an ounce late in New York on Wednesday. It had fallen to as low as $619.60 on Thursday.

"Many analysts expect gold to continue to remain within a narrow range going into year-end with market conditions remaining illiquid," said Investec Australia in a daily report.

"However, this should not be taken as a given, as relatively small volumes have the ability to move the market substantially during these illiquid periods," said Investec, which pegged support around $615 an ounce.

Benchmark gold futures on the Tokyo Commodity Exchange, currently December 2007, rose ¥2 per gram to ¥2 392.

The dollar held steady ahead of the release of the final reading of US third-quarter gross domestic product at 13:30 GMT and the Philadelphia Federal Reserve's manufacturing survey for December at 17:00 GMT.

The euro inched up to $1.3188. The dollar edged down to ¥118.35 but was within sight of a six-week high of ¥118.52 hit in the previous session.

Dealers said the data could help the market to better assess whether the Fed will cut rates in 2007. Lower US interest rates lessen the opportunity cost to investors of holding zero-yielding gold.

In other precious metals, silver edged down to $12.51/12.58 an ounce from $12.52/12.59 an ounce in New York.

Platinum rose to $1 121/1 126 an ounce from $1 118/1 126 an ounce and off Monday's low of $1 093 - the metal's lowest level since early November.

Chinese jewellery makers bought platinum at lower levels this week but retail investors, especially those in Japan, remained cautious after talk about the launch of an exchange-traded fund turned out to be unfounded.

"People are still afraid to buy platinum at this moment. But once the shock caused by the ETF talk is over, they will come back," said a dealer in Tokyo.

"I personally think we should rebound to $1,150 by the end of the year," said the dealer, referring to a level last seen in early December.

Rumours about the ETF launch propelled platinum to a record high of $1 395 an ounce in late November.

Palladium was barely changed at $323/328 an ounce.