COMMODITIES-Down broadly; sugar's weekly slump most in a year

* Sugar down 7 pct on week, biggest drop since Sept 2011
* Copper, gold suffer biggest weekly loss in two months
* Oil, grains down for the day but up on the week

By Barani Krishnan
NEW YORK, Oct 12 (Reuters) - Commodities mostly posted
losses in trading on Friday and were generally lower on the week
as slowing global growth crimped demand for raw materials.
Sugar led the decline with its worst weekly drop in more
than a year.
Copper posted its biggest weekly fall in two months
on worries that top metals consumer China might not be able to
sustain its current pace of buying as growth cools in the
world's second-largest economy.
"There's quite a debate out there right now about the extent
of the economic slowdown in China and what real impact this is
having on metals demand," said Stephen Briggs, metals strategist
at BNP Paribas in London.
Gold prices had their biggest weekly loss
since June as better U.S. consumer sentiment and improved jobs
data stirred worries that the Federal Reserve might pull back
its bullion-friendly stimulus program sooner than expected.

Oil and grains futures also ended Friday's session lower,
but were up for the week on supply concerns for Brent crude oil
and corn.
The Thomson Reuters-Jefferies CRB index, a global
commodities benchmark, ended down 0.7 percent on the day and 0.4
percent on the week.
Fifteen of the 19 markets tracked by the CRB were down for
the day, with nickel losing nearly 4 percent and wheat and corn
about 3 percent each.

Raw sugar fell 2 percent with the front-month contract in
New York settling at 20.05 cents per lb, its lowest close
since Sept. 20.
For the week, the market was down nearly 7 percent - its
sharpest weekly decline since September 2011 - as funds once
bullish on sugar turned negative after "washouts" by Chinese and
Indian sugar buyers. Washouts occur when buyers pay a penalty to
give up the obligation to take delivery.
"The trigger was the washouts," said Michael McDougall, a
vice president for brokerage Newedge USA. "It caused the funds,
like a school of fish, to quickly turn around and head back down
to a negative stance. They reversed course and the market's
feeling it."
Prices at 3:58 p.m. EDT (1958 GMT)
LAST/ NET PCT YTD
CLOSE CHG CHG CHG
US crude 91.78 -0.29 -0.3% -7.1%
Brent crude 114.72 -0.99 -0.9% 6.8%
Natural gas 3.611 0.007 0.2% 20.8%

US gold 1759.70 -10.90 -0.6% 12.3%
Gold 1754.55 -13.64 -0.8% 12.2%
US Copper 370.30 -4.85 -1.3% 7.8%
LME Copper 8130.00 -109.50 -1.3% 7.0%
Dollar 79.670 -0.105 -0.1% -0.6%

US corn 752.75 -20.50 -2.7% 16.4%
US soybeans 1522.00 -26.50 -1.7% 27.0%
US wheat 869.25 -27.75 -3.1% 33.2%

US Coffee 161.70 0.95 0.6% -29.1%
US Cocoa 2366.00 15.00 0.6% 12.2%
US Sugar 20.05 -0.40 -2.0% -13.7%

US silver 33.669 -0.413 -1.2% 20.6%
US platinum 1659.30 -30.30 -1.8% 18.1%
US palladium 639.05 -11.85 -1.8% -2.6%