* TSX down 0.72 of a point, to end at 12,815.91 * Five of the 10 main sectors higher * RIM shares off 7.6 pct ahead of BlackBerry 10 launch By Solarina Ho TORONTO, Jan 28 (Reuters) - Canada's main stock index finished little changed on Monday, as gains in the financial group were offset by declines in natural resource stocks and shares of Research In Motion Ltd,. RIM's critical launch of its new BlackBerry 10 platform will take place this week. The stock was down 7.6 percent to C$16.27, after closing on Friday with a gain of about 50 percent for this year. The overall technology group was down 2.7 percent. But financial stocks gained, as market sentiment has risen lately following a string of encouraging economic data. The financial group, which accounts for about a third of the index, was up 0.5 percent. Royal Bank of Canada climbed 0.8 percent to C$62.61. Bank of Nova Scotia rose 0.8 percent to C$58.95. Five of the top 10 most influential gainers in the index were top Canadian banks. "You're seeing a little bit of a rotation perhaps to more economic sensitive areas of the market, just based on some of the economic optimism over the last few weeks," said Youssef Zohny, portfolio manager at Stenner Investment Partners of Richardson GMP in Vancouver. "We're seeing a pretty sharp rally over the last few weeks. I think the market's either taking a breather or potentially setting up for a mild correction." The Toronto Stock Exchange's S&P/TSX composite index finished 0.72 of a point lower, to end at 12,815.91. Advancers and decliners were evenly split among the index's 10 main groups. "There's still a lot of cash on the sidelines. Any sort of pullback is going to met with buying, but cautious buying," said Ian Nakamoto, director of research at MacDougall, MacDougall & MacTier. Also keeping the TSX in check was the materials sector, which was down nearly 0.9 percent. Potash Corp led the slump, down 1.3 percent at C$43.37. The fertilizer maker had climbed 6.8 percent in the previous five sessions. Barrick Gold Corp was off 0.8 percent to C$32.76, while Kinross Gold Corp fell 2.6 percent to C$8.36. Gold miners tracked softer gold prices, which were holding near two-week lows ahead of the U.S. Federal Reserv's policy meeting on Tuesday on Wednesday. Energy stocks were mixed. The overall group was off just shy of 0.1 percent, despite firmer oil prices. In corporate news, Nordion Inc, a major provider of medical isotopes, said on Monday it has hired advisers to examine options for its future. The shares rose as much as 15 percent, before settling up 7.3 percent, at C$6.90.