Gold in New York gained the most since June on speculation that China will boost purchases of the precious metal to diversify its foreign-exchange reserves.
The dollar tumbled against the euro after Reuters reported the People's Bank of China may switch some of its currency reserves. Gold, sold in dollars, generally moves in the opposite direction of the dollar. The metal is up 23 percent this year while the U.S. currency fell 7.7 percent against the euro.
``China indicated many options are being considered, and the market is inferring some reserves will go into gold,'' said James Vail, who manages $800 million in natural-resource stocks at ING Investments LLC in New York.
Gold futures for December delivery rose $18.50, or 3 percent, to $636.80 an ounce at 1:25 p.m. on the Comex division of the New York Mercantile Exchange. A close at that price would mark the biggest gain for a most-active contract since June 30. Prices fell 1.5 percent yesterday.
``All central banks are trying to diversify,'' People's Bank of China Governor Zhou Xiaochuan said at a conference in Frankfurt. ``We have had a very clear diversification plan for several years.''
China is the tenth-biggest holder of gold reserves. About 1.3 percent of the country's reserves are gold and 72 percent of the reserves are U.S. assets. China's trade surplus with the U.S. helped drive the country's foreign currency reserves close to $1 trillion.
Dollar Weakness
``I'm worried about a weakening dollar and bullish on gold,'' said Thomas Au, principal at R.W. Wentworth & Co., a New York-based consulting company. ``Apparently, Mr. Zhou and company are, too.''
Gold opened higher as the euro rose earlier against the dollar on speculation the European Central Bank will raise interest rates faster than the Federal Reserve.
This year's 23 percent rally in gold would be the biggest since 2002, and prices have gained every year since 2001, moving in tandem with the euro from 2002 to 2004. Last year, gold gained 18 percent, even as the dollar rose 14 percent against the euro.
Gold also gained today on expectations international- investor demand for the dollar may drop after a shift in control of the U.S. Congress. Democrats took control of the House of Representatives after 12 years of Republican rule.
``With the change in Congress, and an inferred anti- business climate, the foreign investors are souring on the dollar,'' ING's Vail said.
`Inflationary Pressure'
Higher crude-oil prices also boosted gold's appeal as a hedge against energy costs, analysts said.
``When oil makes a big move up, it's going to be supportive for gold because of the inflationary pressures,'' said Tom Hartmann, a commodity broker at Altavest Worldwide Trading Inc. in Mission Viejo, California.
Oil rose as much as 2.4 percent to $61.26 a barrel today in New York after gaining 1.5 percent yesterday.
Gold and oil often move together. Gold futures touched $873 an ounce in January 1980 after oil costs doubled in a year, sparking a surge in the inflation rate.
Price charts also indicated gold may climb, some analysts said. The metal has traded above its 200-day moving average since Nov. 1.
``Gold has taken on a life of its own,'' said Matt McKinney, a commodity broker at Infinity Brokerage Services in Chicago. ``If it gets any help from a weaker dollar or stronger oil, that would surely catapult it.''