* TSX up 54.83 points, or 0.44 percent, at 12,618.92
* Seven of the index's 10 sectors higher
* Canada GDP data helps underpin rise (Adds details, quote)
By Jennifer Kwan
TORONTO, Oct 29 (Reuters) - Toronto's main stock index rose on Friday morning as mining shares displayed strength and data showed the Canadian economy returned to growth in August after stalling in July.
Gross domestic product climbed 0.3 percent in August after shrinking 0.1 percent in July, the first contraction in a year. [ID:nN29434455]
Shares of miners climbed even as underlying commodity prices were mixed. [FRX/] Gold miner Barrick Gold ABX.TO rose 1.4 percent to C$48.73, and base-metals miner Teck Resources TCKb.TO climbed 1 percent to C$45.74.
Elsewhere, fertilizer producer Potash Corp POT.TO rose 1.9 percent to C$148.73, and Blackberry maker Research In Motion RIM.TO was up 1.1 percent at C$57.95.
At 10:18 a.m. (1418 GMT), the S&P/TSX composite index .GSPTSE was up 54.83 points, or 0.44 percent, at 12,618.92, with seven of its 10 main sectors higher. It opened slightly lower.
Andrew Pyle, wealth advisor at ScotiaMcLeod, said the market was cautious ahead of U.S. Federal Reserve meetings next week, which could result in more monetary policy easing, as well as the U.S. midterm elections. Also on tap are U.S. and Canadian employment data.
"I really think you're seeing some gyrations into month end. I think you're going to see this all day. There's this cautionary theme going through the market as we head into a massive week next week," he said.
"Investors are aware a lot of asset classes are getting overvalued, stocks, metals, golds, bonds, and believe one if not all events has the potential to derail one of those asset classes."
Brookfield Office Properties BPO.TO shed 0.3 percent to C$17.82, even after it reported a 37 percent rise in quarterly funds from operations (FFO) on Friday, helped by an increase in the number of square feet leased. [ID:nN28225013]
Canada's Silver Standard Resources Inc SSO.TO, up 3.2 percent at C$24.82, said it will sell its Snowfield and Brucejack projects in northern British Columbia to Pretium Resources Inc, a company led by its former CEO Robert Quartermain, for C$450 million in cash and stock. [ID:nSGE69S0DS]
($1=$1.02 Canadian) (Reporting by Jennifer Kwan; editing by Peter Galloway)