CHICAGO, Dec. 8 (Xinhua) -- Gold futures on the COMEX Division of the New York Mercantile Exchange ended lower for the third session on Tuesday as dollar rose. Silver and platinum both fell.

    The most active gold contract for February delivery slumped 20.60 U.S. dollars, or 1.8 percent, to finish at 1,143.40 dollars an ounce.

    Dollar regained strength as investors continued to buy this precious metal as hedge assets against the greenback's depreciation, especially after the Federal Reserve Chairman Ben Bernanke warned that it's too soon to know whether the economic recovery will last and again pledged to hold rates at extra-low levels for an "extended period."

    The dollar index, a gauge measuring the greenback's value against the other major currencies, rallied about 0.6 to 76.235 by the end of gold floor trading time, which strengthened gold's appeal of hedge.

    March silver was down 55.3 cents to 17.807 dollars per ounce. January platinum dropped 4.20 dollars to 1,440.40 dollars an ounce.