Copper prices continued to rally Thursday, hitting a two-month high as big U.S. manufacturers say they're optimistic about the economy.
In other active trading, an extreme Russian drought supported wheat prices, which have rallied about 25 percent this month. Prices touched a 13-month high.
Copper for September delivery rose 7.15 cents, or 2.3 percent, to settle at $3.1645 a pound, hitting its highest price since May 14. They have risen nearly 6 percent this week.
Copper prices had peaked in January above $3.50 a pound, falling below $3 earlier this spring and summer as uncertainty about the recovery hit investors.
Industrial metals such as copper are used in manufacturing and construction. Strong economic growth would mean more production at factories and more building, boosting demand for the metal and its production.
George Gero, vice president at RBC Global Futures in New York, credited recent optimistic outlooks from big manufacturers for driving copper's gains.
Heavy machinery maker Caterpillar Inc. said Thursday that orders were growing and it would increase production in the second half of the year. It raised its profit outlook.
Other strong forecasts from UPS Inc., AT&T Inc. and 3M Co. Thursday helped drive the stock market higher as investors priced in better expectations for an economic recovery.
Automaker Fiat, which controls Chrysler, said Wednesday it posted a profit in the second quarter because of improved sales of farm equipment and trucks.
Copper is an important component of wiring and parts in autos, as well as telecommunications and industrial equipment.
Other metals contracts mostly edged higher as the dollar tumbled and stock prices rallied. A stronger dollar makes commodities that are based in dollars more expensive for foreign buyers.
Silver for September delivery rose 31.7 cents, or 1.8 percent, to end at $18.120 an ounce, while September palladium gained $4.75 to settle at $456.90 an ounce. October platinum ended almost flat, however, dipping 40 cents to settle at $1,529.40 an ounce.
Gold for August delivery rose $3.80 to settle at $1,195.60 an ounce.
Wheat prices also continued to rally as weather forecasters saw no end in sight to the drought hitting Russia, Ukraine and Kazakhstan. Russia is suffering its worst drought in 130 years, which has already destroyed 20 percent of the country's grain crop. Russia is the world's No. 3 wheat exporter.
"As long as the crop is getting smaller, the price is probably going to keep advancing," said Richard Feltes, director of commodity research for MF Global in Chicago. The U.S. is expected to have a strong crop this year, while Canada got hit by extremely wet weather and Russia is suffering from the drought.
"We should start to get more export business," said Jason Ward, an analyst with Northstar Commodity in Minneapolis. "For a U.S. producer, it's probably the best thing you could ask for: A good crop potential and a price that continues to rally."
Wheat for September delivery rose 8.25 cents, or 1.4 percent, to $5.965 a bushel. Prices have risen about 25 percent in July, and hit their highest level Thursday since June 2009.
Some don't expect the rally to last, however, since there is plenty of wheat supply in the U.S.
In other agricultural futures, corn for September delivery fell 3.25 cents to $3.765 a bushel, while soybeans for November delivery gained 1 cent to $9.795 a bushel.
Energy prices got a boost from the positive earnings reports as well as a developing tropical storm that could hit the Gulf of Mexico this weekend.
Benchmark crude for September delivery jumped more than $2.74, or 3.6 percent, to settle at $79.30 a barrel on the New York Mercantile Exchange.
Other energy contracts also veered higher. Natural gas gained 13 cents at to settle at $4.643 per 1,000 cubic feet; heating oil rose 7.32 cents to settle at $2.0624 a gallon and gasoline added 7.88 cents to settle at $2.1466 a gallon.