Corn prices fell sharply Thursday, continuing a seesaw week.
Corn for December delivery dropped 18.75 cents, or 3.9 percent, to $4.65 a bushel Thursday.
The price has bounced around this week, as forecasts for dry weather in the Midwest counter predictions that this year's corn harvest will rebound after last year's drought.
In trading of other agricultural products, soybeans and wheat also dropped more than 1 percent.
Metals were higher.
Copper for September delivery rose 2.3 cents to $3.33 a pound. Silver for the same month gained 7.2 cents to $23.04 an ounce. Gold for December rose 70 cents to $1,370.80 an ounce.
Platinum for October gained $21 to $1,540.10 an ounce. September palladium rose $8.15 to $755.05 an ounce.
In energy trading, the price of oil rose for the first time this week, gaining $1.18, or 1.1 percent, to $105.03 a barrel, thanks to strong manufacturing data from China and Europe.
Gasoline futures rose 3 cents to $2.95 a barrel. Heating oil dropped 1 cent to $3.07 per gallon. Natural gas rose 9 cents to $3.55 per 1,000 cubic feet.