* TSX falls 6.12 points, or 0.05 percent, to 13,472.22 * Six of 10 main index sectors advance * BlackBerry rises after executive shakeup * Detour Gold drops after CEO resigns By John Tilak TORONTO, Nov 25 Canada's main stock index was little changed on Monday after a deal aimed at restricting Iran's nuclear program fueled broad market gains but weighed on the price of oil and on shares of energy companies. Also stirring the market, BlackBerry Ltd shares jumped after the company announced another shakeup in the executive suite. Much of the market remained focused on the accord announced Sunday between Iran and six western nations and its aftermath. U.S. President Barack Obama sought to persuade Israel of the agreement's merit, while moves were made to try to turn the interim deal into a comprehensive one. The markets view the deal as a positive as it helps keep the lid on the price of oil, said Bob Gorman, chief portfolio strategist at TD Wealth. "It's very unlikely that you'll see significant upward pressure in the price of oil, and in aggregate that is a good thing for the global economy." The Toronto Stock Exchange's S&P/TSX composite index closed down 6.12 points, or 0.05 percent, at 13,472.22. The benchmark Canadian index remained up about 8 percent so far this year. Gorman, who expects the Toronto market to produce returns of about 7 percent next year, said investors should look beyond the near-term moves to see select opportunities in the commodity sectors as valuations have come down. His top picks across sectors include Bank of Nova Scotia, Suncor Energy Inc and Teck Resources Ltd. "On the resource side, the downside is probably limited and you'll see better relative performance going forward," he said. "That in turn means good things for the market and the Canadian economy in general." Six of the 10 main sectors on the index were higher on Monday. The industrial sector added 0.5 percent, with Canadian Pacific Railway Ltd gaining 1.3 percent to C$161.11 and Canadian National Railway Co rising 0.6 percent to C$119.61. Oil prices dropped after the Iran deal, weighing on shares of energy producers. Suncor gave back 1.9 percent to C$37.24 and had the biggest negative influence on the index. Canadian Natural Resources Ltd lost 0.9 percent to C$34.52. "It's potentially a longer-term negative for (energy stocks) with more Iranian production coming back on," said David Cockfield, managing director and portfolio manager at Northland Wealth Management. Gold-mining stocks were virtually unchanged after the bullion price had a volatile session. Goldcorp Inc declined 0.4 percent to C$24.21, but Barrick Gold Corp climbed 0.5 percent to C$17.29. Detour Gold Corp dropped 11.7 percent, to C$3.77, after the miner said Chief Executive Gerald Panneton had resigned. BlackBerry said two top executives were departing and a third was replaced in a widely expected shakeup following this month's naming of a new chief executive, and that more changes were coming. The stock gained 1.4 percent to C$6.60. Saputo Inc declared its A$505 million ($463 million) bid for Warrnambool Cheese and Butter Factory Co unconditional and said it would hike its offer if it won control of Australia's oldest dairy. Shares of the Canadian company rose 0.1 percent to C$48.60.