The Standard & Poor’s GSCI gauge of 24 commodities fell 0.4 percent to settle at 653.61 at 4 p.m. in New York, paced by grains and soybeans.
The UBS Bloomberg CMCI index of 26 raw materials declined 0.7 percent to 1,555.55.
Corn fell the most in five weeks on speculation that demand is slowing after a crop-damaging U.S. drought sent prices to a record this month. Soybeans and wheat declined as rain aided parched fields from Kansas to Ohio.
On the Chicago Board of Trade, corn futures for December delivery tumbled 2.1 percent to $7.9225 a bushel, the largest drop for the most-active contract since July 6.
Soybean futures for November delivery fell 2.6 percent to $16.0075 a bushel in Chicago, the first drop in four sessions.
Wheat futures for December delivery slumped 2.8 percent to $8.7575 a bushel, the biggest decline since July 31.
Copper fell to a one-week low on signs that demand growth is slowing in China, the world’s largest consumer of the metal.
On the Comex in New York, copper futures for September delivery slid 1.1 percent to $3.3535 a pound, after dropping to $3.342, the lowest since Aug. 3.
On the London Metal Exchange, copper for delivery in three months slumped 1.3 percent to $7,395 a metric ton ($3.35 a pound), the biggest drop since Aug. 2. Aluminum, tin, nickel, zinc and lead also declined in London.
Gold fell for the first time in four sessions, tracking losses in commodities and equities, amid increasing concern that global growth is stagnating.
On the Comex, gold futures for December delivery dropped 0.6 percent to $1,612.60 an ounce.
Silver futures for September delivery retreated 1.1 percent to $27.767 an ounce.
On the New York Mercantile Exchange, platinum futures for October delivery slipped 0.5 percent to $1,392.80 an ounce. Palladium futures for September delivery slumped 1.3 percent to $574.70 an ounce.
Crude oil retreated for a second day as U.S. equities dropped and as Japan’s economy grew more slowly than expected.
On the New York Mercantile Exchange, oil futures for September delivery slid 0.2 percent to $92.73 a barrel.
Brent oil for September settlement advanced 0.6 percent to $113.60 a barrel on the London-based ICE Futures Europe exchange. The European benchmark’s premium to West Texas Intermediate in New York widened to $20.87 a barrel, a four- month high.
BP Plc (BP/) failed to sell cargoes of North Sea Forties and Ekofisk crudes. Total SA was unsuccessful in its bid for Forties.
Daily exports of the 12 main grades of North Sea crude for loading in September will slump to the lowest level in more than four years because of planned field maintenance.
Gasoline dropped on speculation that fuel supplies will increase in the Midwest and maintenance at California refineries may be delayed.
On the Nymex, gasoline futures for September delivery fell 0.4 percent to settle at $2.9907 a gallon.
Heating-oil futures for September delivery slid 0.1 percent to $3.0183 a gallon.
Natural gas declined to the lowest in more than six weeks as forecasts for cooler weather signaled reduced demand for the power-plant fuel to run air conditioners.
On the Nymex, gas futures for September delivery slid 1.5 percent to $2.729 per million British thermal units, the lowest close since June 28.
U.K. natural gas for within-day delivery advanced for a sixth day as imports from Norway declined.
Same-day gas rose 0.85 pence, or 1.6 percent, to 55.35 pence a therm at 4:45 p.m. London time, after touching 55.6 pence, the most since July 17. September gas advanced 0.4 percent to 56.7 pence a therm. That’s equivalent to $8.90 per million British thermal units. A therm is 100,000 Btu.
Arabica-coffee futures fell to the lowest since June on signs of improving supplies in Colombia, the world’s second- largest grower of the beans.
On ICE Futures U.S. in New York, arabica-coffee futures for December delivery dropped 1.4 percent to $1.6705 a pound, after reaching $1.66, the lowest for a most-active contract since June 29.
Cotton futures for December delivery slid 1.8 percent to 71.69 cents a pound.
Raw-sugar futures for October delivery slipped 1.7 percent to 20.39 cents a pound, the 10th straight decline and the longest slide since May 1989.
Cocoa futures for December delivery retreated 2.4 percent to $2,399 a ton.
Orange-juice futures for November delivery sank 1.9 percent to $1.045 a pound.
Cattle futures jumped to a five-month high on signs of increasing U.S. demand for beef before the Labor Day holiday, when many consumers grill outdoors.
On the Chicago Mercantile Exchange, cattle futures for October delivery increased 0.7 percent to $1.26375 a pound, after reaching $1.267, the highest for a most-active contract since March 8.
Feeder-cattle futures for October settlement advanced 1.8 percent to $1.43475 a pound. Earlier, the price rose by the 3- cent exchange limit to $1.43875, the highest since July 12.
Hog futures for October settlement rose 2 percent to 77.05 cents a pound, marking the biggest gain for the most-active contract since July 25.
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