(Refiles to fix spelling of commodity in headline)
* TSX down 3 percent on day, 5.6 percent for week
* Energy sector sags as crude slides to $57.04
* RIM, Nortel help drag technology sector down
* Canwest drops 8.8 percent after quarterly results (Adds quote, details)
By Jennifer Kwan
TORONTO, Nov 14 (Reuters) - The Toronto Stock Exchange's main index retreated broadly on Friday, led lower by weakness in energy and materials issues as gloomy U.S. retail sales data heightened worries about a deeper economic downturn.
Heavily weighted stocks that helped push the key index lower included EnCana Corp (ECA.TO) and Research In Motion RIM.TO.
The energy sector was a major source of weakness, down 3.2 percent as the price of oil dropped to $57.04 a barrel on dismal U.S. economic data and on expectations of further weakness in demand as the euro zone slipped into a recession. [ID:nSP399460] EnCana fell 5.8 percent to C$54.75.
The materials group was off 5.9 percent, helped lower by fertilizer producer Agrium Inc (AGU.TO), which retreated 7.4 percent to C$40.49. [ID:nN14451596]
Potash Corp of Saskatchewan (POT.TO), the world's biggest fertilizer producer, was down 4.2 percent at C$86.12 even though Potash workers ratified a new three-year contract this week at three Saskatchewan mines. [ID:nN14442189]
The S&P/TSX composite index .GSPTSE closed down 296.82 points, or 3.17 percent, at 9,055.96, with all but two of its 10 main groups in the red. Consumer staples rose 0.08 percent, while utilities were up 0.3 percent.
The index was down 5.6 for the week, its weakest showing since Oct. 10.
The index fell as U.S. retail sales suffered a record decline in October. A separate report showed consumer sentiment improved in November, but that consumers were still on the defensive. [ID:nN14423234]
"Consumer confidence is still on the weak side in the U.S. Retail sales are also weaker than expected. Not any good reasons to be overly enthusiastic," said Francis Campeau, broker at MF Global Canada, in Montreal.
"The picture going forward still looks a bit bleak."
The information technology group sank 6.7 percent as RIM fell 7.9 percent to C$49.37 and Nortel Networks NT.TO dropped 17.8 percent to 74 Canadian cents.
Canwest Global Communications CGS.TO, Canada's biggest media company, posted a steep quarterly loss on Friday [ID:nN14417750] and its shares fell 8.8 percent to 73 Canadian cents.
On Wall Street, U.S. stocks sold off as concerns mounted that Americans' reluctance to spend will push the economy into a deeper downturn. [ID:nN14454422]
The Dow Jones industrial average .DJI fell 337.94 points, or 3.82 percent, at 8,497.31, while the Nasdaq Composite Index .IXIC ended down 79.85 points, or 5.0 percent, at 1,516.85. ($1=$1.23 Canadian) (Reporting by Jennifer Kwan; Editing by Peter Galloway)