Precious metals prices fell early Thursday, but they turned around and closed higher in New York after an unfavorable economic report dented the dollar. Benchmark contracts for gold bullion gained $8.10 at $743.80 an ounce, while silver contracts were up 3 cents at $13.50 an ounce. Prices for both metals declined at the start of the session. However, they reversed course after a Commerce Department report showed that U.S. factory sector activity fell more than expected during August. That sent the value of the greenback spinning lower and helped boost the prices for dollar-denominated assets such as gold and silver. "All it takes is one more bit of evidence of economic anemia on the occasional trading day to throw funds into a tizzy," writes Jon Nadler, an analyst at Montreal-based bullion dealer Kitco. Meanwhile, copper prices moved south, with benchmark contracts off 3 cents at $3.74 a pound on concerns that a slowing manufacturing sector would reduce demand for the metal. In other commodities, wheat prices were off 2.3% at $9.06 a bushel, after a new report said Canada's harvest would be larger than previously reported. Frozen concentrated orange juice contracts gained 2.2% at $1.37 a pound. As for the commodity stocks, Harmony Gold Mining ( HMY) climbed 2.9% on news that about 2,000 of roughly 3,200 trapped miners had been rescued after an accident at a deep underground mine in South Africa.