* TSX ends down 59.50 points, or 0.48 pct, at 12,284.31
* Nine of 10 main sectors weaker, golds boost materials (Updates to close, adds details, comments)
By Claire Sibonney
TORONTO, Aug 25 (Reuters) - Toronto's main stock index ended lower in volatile trade on Thursday as anxiety gripped investors over the economic outlook and what U.S. Federal Reserve Chairman Ben Bernanke would say in a highly anticipated speech on Friday.
A report showing U.S. job market weakness and concerns over a sharp drop in German stocks were the latest global economic concerns, fueling a wave of selling in equity markets.
Energy issues were the biggest drag on the the index, with Suncor Energy SU.TO, the heaviest decliner, fell 2.4 percent to C$29.54, while Canadian Natural Resources CNQ.TO lost 1.9 percent to C$34.40.
Sentiment was also hurt by a drop in shares of U.S. heavyweight Apple Inc AAPL.O, a day after co-founder Steve Jobs resigned as chief executive. [.N] That news initially helped lift shares of rival Research In Motion RIM.TO but RIM soon succumbed to the negative sentiment and fell 1.3 percent to C$27.89.
The Toronto Stock Exchange's S&P/TSX composite index .GSPTSE ended down 59.50 points, or 0.48 percent, at 12,284.31. Nine of the 10 main sectors were lower, while materials gained 1.2 percent on the back of rallying golds.
Precious-metal shares were the lead gainers on the day, and helped the TSX outperform its U.S. counterparts [ID:nN1E77O1R9], as the price of gold rebounded on safe-haven bids, after two days of sharp declines. [GOL/]
Barrick Gold ABX.TO was the most heavily weighted climber, up 2.3 percent to C$49.37, followed by Goldcorp Inc G.TO, up 2.7 percent at C$50.60.
Financials, which ended down 0.8 percent, had initially led the index higher, supported by news that Warren Buffett's Berkshire Hathaway BRKa.N will invest $5 billion in Bank of America Corp BAC.N, and on optimism for domestic bank earnings after a higher than expected profit posted by Bank of Montreal BMO.TO on Tuesday.
National Bank of Canada NA.TO shed 2.7 percent to C$70.40, despite reporting on Thursday that quarterly profit rose 15 percent, as analysts voiced concerns over narrower margins on loans and weak trading revenues. [ID:nN1E77O06N]
Traders were on edge before Bernanke's speech on Friday to central bankers in Jackson Hole, Wyoming. Many are waiting to see whether the Fed chief will provide concrete action for further monetary stimulus or simply outline general guidelines for supporting the struggling U.S. economy. [FED/AHEAD]
"Nobody knows what Bernanke is going to say tomorrow ... my expectations are not terribly high," said David Baskin, president of Baskin Financial Services.
"I don't think he's going to say anything revolutionary, that would be odd for the Fed," Baskin added, noting investors were also likely profit-taking on Thursday following healthy gains earlier in the week.
Kate Warne, Canadian market strategist at Edward Jones in St. Louis, Missouri, said it's much more likely that Bernanke will simply go through a laundry list of actions the Fed might be able to take if conditions deteriorate.
"We could either see a negative market reaction because there are expectations that the Fed will pull a rabbit out of the 'hole' so to speak," she said.
"But I think the other side is that investors could take it as good news that the Fed is saying that even though we've seen many weak indicators, that we don't think the economy needs more right now."
($1=$0.99 Canadian) (Reporting by Claire Sibonney; editing by Rob Wilson)