The Standard & Poor’s GSCI gauge of 24 raw materials fell 1.1 percent to settle at 630.33 at 4 p.m. in New York, led by natural gas.
The UBS Bloomberg CMCI index of 26 prices declined 1.4 percent to 1,529.01.
Natural gas tumbled the most in almost three years after a government report showed that U.S. stockpiles rose more than expected last week.
The Energy Department said inventories rose 28 billion cubic feet in the week ended July 27 to 3.217 trillion cubic feet. Analyst estimates compiled by Bloomberg predicted a gain of 23 billion.
On the New York Mercantile Exchange, gas futures for September delivery fell 7.9 percent, the biggest decline since Sept. 17, 2009, to $2.92 per million British thermal units.
U.K. natural gas for prompt delivery declined as liquefied fuel shipments from the U.K.’s South Hook terminal stayed near a three-month high. Day-ahead power fell.
Within-day gas dropped for a third day, by 1.5 percent to 51.7 pence a therm, according to broker data compiled by Bloomberg. September gas fell 0.6 percent to 54.35 pence a therm. That’s equivalent to $8.43 per million British thermal units. A therm is 100,000 Btu.
Oil fell in New York after European Central Bank President Mario Draghi failed to give details of a plan designed to shore up the euro by curbing rising government borrowing costs in the region.
On the Nymex, oil futures for September delivery slumped 2 percent to $87.13 a barrel.
Brent crude for September settlement slipped 6 cents to $105.90 a barrel on the London-based ICE Futures Europe exchange.
Vitol Group purchased its fourth North Sea Forties crude cargo for loading in August at the highest price in almost one month, while BP Plc (BP/) sold an Ekofisk shipment. Socar Trading SA failed secure a buyer for an Azeri Light lot in the Mediterranean for the second day.
Three out of 10 consignments of Nigerian Qua Iboe crude for loading in September remain unsold, according to four traders who participate in the market.
Gasoline rose on concern a spate of refinery outages will curtail supply and a day after the Energy Department said inventories sank the most since May.
On the Nymex, gasoline futures for September delivery climbed 1.3 percent to $2.8696 a gallon.
Heating-oil futures for September delivery fell 0.6 percent to $2.8423 a gallon.
Copper fell to a five-week low in New York after the European Central Bank failed to announce additional measures to stimulate the region’s flagging economic growth, eroding demand prospects for metals.
On the Comex in New York, copper futures for September delivery declined 2.5 percent to $3.2905 a pound, after touching $3.2885, the lowest for a most-active contract since June 25.
On the London Metal Exchange, copper for delivery in three months slipped 1.3 percent to $7,330 a metric ton ($3.32 a pound). Aluminum, zinc, tin lead and nickel were also lower in London.
Gold fell the most in two weeks amid investor disappointment with European Central Bank President Mario Draghi’s comments on efforts to fight the debt crisis.
On the Comex, gold futures for December delivery dropped 1 percent to $1,590.70 an ounce, the biggest decline for a most- active contract since July 18.
Silver futures for September delivery tumbled 2 percent to $26.995 an ounce, the biggest drop since July 10.
On the New York Mercantile Exchange, platinum futures for October delivery slipped 1 percent to $1,387.80 an ounce. Palladium futures for September delivery fell 2.5 percent to $567.85 an ounce.
Corn fell for a third straight day, capping the longest losing streak since June 13, as some lawmakers urged the U.S. to amend an alternative-fuel mandate, dimming prospects for demand.
On the Chicago Board of Trade, corn futures for December delivery dropped 0.6 percent to $7.9575 a bushel.
Soybean futures for November delivery retreated 0.8 percent to $16.165 a bushel.
Wheat futures for September delivery tumbled 1.6 percent to $8.65 a bushel.
Sugar slumped to the lowest in almost four weeks as dry weather eased supply concerns in Brazil, the world’s top producer.
On ICE Futures U.S. in New York, raw sugar for October delivery fell 2.3 percent to 22.04 cents a pound, after touching 21.95 cents, the lowest for a most-active contract since July 6.
Cocoa futures for September delivery retreated 1.3 percent to $2,369 a metric ton.
Arabica-coffee futures for September delivery lost 1.7 percent to $1.7165 a pound.
Orange-juice futures for September delivery increased 1.5 percent to $1.0925 a pound.
Cotton futures for December delivery advanced 0.6 percent to 70.97 cents a pound in New York.
Hog prices fell for the third straight day, reaching a one- week low on speculation that U.S. pork supplies are outpacing demand.
On the Chicago Mercantile Exchange, hog futures for October settlement declined 1.9 percent to 78.225 cents a pound, after reaching 78.2 cents, the lowest since July 25.
Cattle futures for October delivery rose 0.8 percent to $1.251 a pound.
Feeder-cattle futures for October settlement declined 0.2 percent to $1.42025 a pound.
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