Aug. 17 (Bloomberg) -- Gold and silver prices declined in Asia as falling share markets spurred investors to sell assets to raise cash.

Asian stocks fell for a fourth day as the MSCI Asia-Pacific Index extended losses. Eighteen of 19 commodities in the Reuters/Jefferies CRB Index declined yesterday as equity markets around the world tumbled, sending benchmark indexes in Europe and Asia to the lowest in five months.

``Commodities fell across the board and everything is getting smacked,'' Jonathan Barratt, managing director at Commodity Broking Services in Sydney, said by phone today.

Bullion for immediate delivery fell as much as $5.61, or 0.9 percent, to $646.40 an ounce and traded at $649.20 at 10:32 a.m. Singapore time. Silver for immediate delivery declined 0.7 percent to $11.70 an ounce.

Barratt said he may revise his forecast for gold this year if bullion breaks a so-called support level at $642 an ounce. Support is a level on a chart where buy orders cluster.

Gold typically moves in the opposite direction to the dollar, which has gained to two-month highs against the British pound and the euro amid the stocks rout.

``The U.S. dollar continued to benefit from all these disturbances while gold did not,'' according to Jon Nadler, an investment-products analyst at Montreal-based Kitco Minerals & Metals Co. in a report yesterday.

The Japanese currency's rise to a one-year high against the dollar reduced the appeal of yen-denominated gold futures in Tokyo. Gold for delivery in June was down by 120 yen, the maximum allowed in a day, or 4.8 percent, to 2,389 yen a gram (655 an ounce) at the Tokyo Commodity Exchange break.

Gold for December delivery gained $1.10 to $659.10 an ounce at 10:26 a.m. Singapore time on the Comex division of the New York Mercantile Exchange.

To contact the reporter on this story: Feiwen Rong in Singapore at frong2@bloomberg.net

Last Updated: August 16, 2007 23:45 EDT