By The Associated PressCopper prices are rising after two reports boosted optimism that the U.S. economic recovery is gaining traction. U.S. builders started work on homes in December at the fastest pace since the summer of 2008, the Commerce Department said Thursday. The Labor Department also reported that the number of Americans seeking unemployment benefits fell to a five-year low last week. The price of copper, which is used in construction, typically tracks the outlook for global economic growth. "Undoubtedly, the strength in the housing data was certainly supporting the copper market," said Dave Meger at Vision Financial Markets. Traders will also closely follow a series of reports about the Chinese economy, to be published late Thursday, for indications about the outlook for growth in the world's second-largest economy, Meger said. Copper for March delivery rose 5.55 cents to $3.662 a pound in trading Thursday, its second-biggest gain of the month. Gold for February delivery gained $7.60 to $1,690.80 an ounce. Silver for March delivery rose 26.80 cents to $31.81 an ounce. April platinum edged higher, closing $6.40 up at $1,700.50 an ounce. Palladium for March delivery was little changed, dropping 30 cents to $726.15 an ounce. Oil also rose because of growing optimism about the economy. Benchmark crude gained $1.25 to $95.49 a barrel at midday on the New York Mercantile Exchange. That follows a gain of 96 cents Wednesday, which was prompted by concerns about contracting supplies. Natural gas for February rose 5.9 cents to $3.494 per 1,000 cubic feet. March gasoline rose 4.4 cents to $2.7825 per gallon. Heating oil for March delivery rose 2.21 cents to $3.0145 a gallon. In grain trading, wheat for March delivery dropped 3.75 cents to $7.8125 a bushel. March corn fell 6.75 cents to $7.245 a bushel and March corn fell 6.75 cents to $7.245 a bushel.