* TSX falls 99.64 points, or 0.86 percent, at 11,462.87
* Index touches lowest point since July 2010
* Eight of 10 sectors higher; materials, energy weigh (Adds comments, details)
By Trish Nixon
TORONTO, Sept 23 (Reuters) - A selloff in resource-based shares drove Toronto's main stock index to a 2011 low and into bear territory on Friday as growing fears of a global recession and a Greek debt default battered commodities.
The index's heavyweight materials group tumbled 4.4 percent as metals plunged across the board. Gold slumped more than 6 percent, the biggest slide since the financial crisis of 2008, driving the TSX's gold-mining sub-group down 5 percent. [MET/L] [GOL/]
"Golds were for most of the year the big performers, and then fears of the recession, profit-taking, and (U.S. Federal Reserve Chairman Ben) Bernanke's ineffective attempt at propping things up all converged in sending them down," said John Ing, president of Maison Placements Canada.
"These stocks got caught in the downdraft, just like we saw in '08."
Barrick Gold (ABX.TO) was the heaviest decliner, down 4.9 percent at C$47.73, while GoldCorp (G.TO) fell 4.4 percent to C$46.95.
First Quantum Minerals (FM.TO) tumbled 7.3 percent to C$13.71 as copper fell to its its lowest level since August 2010. [MET/L]
The Toronto Stock Exchange's S&P/TSX composite index .GSPTSE ended the session down 99.64 points, or 0.86 percent, at 11,462.87. It touched a session low of 11,355.82, its weakest point since July 2010.
The TSX lost nearly 7 percent of its value this week, as severe anxiety over Europe's spiraling debt crisis and the Fed's dire warning about headwinds facing the U.S. economy triggered three days of heavy selling.
The index has fallen more than 20 percent from the 2011 high it set in March, meeting the definition of a bear market.
"I can say I've never seen the Street as bearish and as gloomy as it is," said Paul Taylor, chief investment officer at BMO Harris Private Banking.
"There is a concern that the issues are not being addressed in a thorough fashion and, if they aren't, the markets will continue to weigh in with their verdict, which is obviously not favorable."
A pledge by G20 policymakers that they will take steps to calm the global financial system failed to appease investors, who are concerned that authorities are unable to respond effectively to the mounting euro zone debt crisis and sluggish growth in major world economies. [ID:nL5E7KN1IW]
Eight of the TSX's 10 main sectors bounced higher on Friday, but energy issues sank a further 1.1 percent as oil fell to six-week lows. Canadian Natural Resources (CNQ.TO) slipped 2.2 percent to C$30.23. [O/R]
The financials group helped cushion the losses as it held on to moderate gains, ending the session up 0.5 percent. Royal Bank of Canada (RY.TO) was the index's most heavily weighted advancer, up 1.6 percent at C$46.09, while Bank of Nova Scotia (BNS.TO) rose 1.5 percent to C$50.73.
"It's sort of the quiet before the storm, we haven't figured out yet what's going to happen with the European banks," Ing said.
"There's the inevitable contagion, and our banks are not immune from the problems overseas or south of the border."
($1=$1.03 Canadian) (Additional reporting by Andrea Hopkins; editing by Peter Galloway and Rob Wilson)