Updated from 3:46 p.m. EDT

Commodities were mixed Friday, with crude oil futures dropping while metals gained ground.

Ahead of OPEC's weekend meeting, oil for April delivery was down 78 cents at $46.25 a barrel in New York trading. Natural gas and heating oil also fell, and reformulated gasoline rose slightly to $1.35 a gallon.

Among agricultural futures, cocoa, corn and frozen concentrated orange juice were stronger, but coffee, soybeans, sugar and wheat were down. Prices for cattle and hogs were up.

Gold rose $6.10 to $930.10 an ounce, and silver advanced 27 cents to $13.22 an ounce. Copper was also higher, as were platinum and palladium. In the foreign exchange market, the dollar was mostly weaker.

Turning to commodity-related stocks, Exxon Mobil ( XOM) was up 5 cents at $67.20, and Chevron ( CVX) was lower by 49 cents, or 0.8%, to $62.91. ConocoPhillips ( COP) lost 98 cents, or 2.6% to $36.41.

Miners Freeport-McMoRan ( FCX), BHP Billiton ( BHP) and Rio Tinto ( RTP) traded to the upside.

Companies in the ag sector tended to be sluggish. Monsanto ( MON) and Potash ( POT) were among those posting declines.

As for exchange-traded funds, the U.S. Oil ( USO) was off 60 cents, or 2.1%, at $27.63, and the Market Vectors Agribusiness ( MOO) slipped 26 cents, or 1%, to $27.07.