$1,700 an ounce and crude oil to a four-month low.
Gold lost $40.30 to settle at $1,675.20 an ounce, the first close below $1,700 since Sept. 5.
Other metals also fell sharply. Silver fell 4 percent, and platinum, palladium and copper each fell 2 percent. Traders cited strong U.S. economic reports which could diminish the chances that the Federal Reserve will further extend its low-interest rate policy.
The U.S. government released two economic reports early Friday that suggested the U.S. economy was continuing to improve. Employers added 171,000 jobs last month, and factory orders increased 4.8 percent. Both were better than analysts had forecast.
The relatively strong signals on the U.S. economy sent the dollar higher against other currencies and led traders to anticipate that the Fed may not keep interest rates at their rock-bottom lows for as long as previously expected.
A stronger dollar and higher expectations for economic growth tend to push down prices for gold and other precious metals. Traders tend to buy gold when they're seeking an alternative to holding dollars and are fearful that the dollar could be weakened by inflation or an extended period of low interest rates.
In other December contracts, silver dropped $1.391 to $30.8570 per ounce, palladium fell $12.80 to $599.65 per ounce and copper lost 7.05 cents to $3.4815 a pound. January platinum decreased $28.30 to finish at $1,544.90 an ounce
Refinery shutdowns helped push down the price of oil and other energy futures. Big refineries owned by Phillips 66 and Hess still aren't operating four days after Superstorm Sandy hit the East Coast.
Oil fell $2.23 to close at $84.86, the lowest since July 10.
In other energy trading, wholesale gasoline futures dropped 6 cents to $2.5736 per gallon, heating oil fell 8.58 cents to $2.9474 per gallon and natural gas dropped 14.5 cents to $3.5540 per 1,000 cubic feet.
Grains and beans futures also closed lower.
In agricultural contracts, December wheat fell 4 cents to finish at $8.645 per bushel, December corn fell 11.5 cents to $7.3950 per bushel and January soybeans lost 33.25 cents at $15.2675 per bushel.