* TSX rises 53.18 points, or 0.43 percent, to 12,323.61 * Eight of 10 main sectors advance * Potash climbs 2.4 percent after results By John Tilak TORONTO, April 25 (Reuters) - Canada's main stock index extended its gains into a sixth straight session on Thursday, buoyed by positive U.S. economic data and a stronger-than-expected earnings report from Potash Corp . Investors were encouraged by data showing the number of Americans filing new claims for unemployment benefits fell last week, offering reassurance that the bottom is not falling out of the labor market. The Toronto market, which posted its biggest jump in more than eight months on Wednesday, has erased most of the losses incurred during a massive commodities-led rout earlier this month. "The TSX is staging a bit of a recovery," said Keith G. Richards, portfolio manager and technical analyst at ValueTrend Wealth Management. "I see this near-term rally as a near-term rally, and that's all." He expects weakness in banks and commodities to hold the index back over the next couple of months. Despite the gains, the index is down 0.9 percent on the year, compared with a 10.7 percent rise in the S&P 500. The Toronto Stock Exchange's S&P/TSX composite index was up 53.18 points, or 0.43 percent, at 12,323.61 on Thursday. It hit its highest point since the huge selloff on April 15. Eight of the 10 main sectors of the index were higher. A 2.4 percent gain in Potash and rise in gold shares boosted the materials sector, which climbed 2.3 percent. The price of bullion hit a 10-day high, lifted by a weak dollar and strong physical buying. Potash said it was abandoning efforts to take over Israel Chemicals Ltd because of strong opposition in Israel. The fertilizer giant also reported a stronger-than-expected 13 percent rise in profit after renewed sales to China and India. "Potash has got near-term upside," Richards said. "Positive news on the stock is going to push it a bit." Energy shares rose 0.5 percent, reflecting a rise in the price of oil. Financials, the index's most heavily weighted sector, gave back 0.2 percent. In other company news, Open Text Corp reported a 25 percent rise in third-quarter adjusted profit as its cloud-based services business expanded. The business software maker's stock added 9.1 percent to C$63.02. Shares of Imperial Oil Ltd climbed 1.4 percent after Canada's No. 2 oil producer and refiner reported a first-quarter profit.