* TSX ends down 53.49 points, or 0.42 percent, at 12,721.79 * Seven of 10 main index sectors decline * BlackBerry shares volatile after former co-CEO sells stake * Barrick climbs 2.3 percent after results By Claire Sibonney TORONTO, Feb 14 (Reuters) - Canada's main stock index fell to a more than one-week low on Thursday as energy stocks declined after data showed Europe falling deeper into recession, offsetting a rise in Barrick Gold Corp as investors found a silver lining in its big quarterly loss. Encana Corp, Canada's largest natural gas producer, plunged 6.6 percent to C$18.20 after it offered a 2013 production target for oil and natural gas liquids that was lower than expected. It played the biggest role of any stock in leading the market lower. The market tracked data that showed the German economy contracted by 0.6 percent in the last three months of 2012, its worst performance since the global financial crisis was raging in 2009. The French economy contracted 0.3 percent, a slightly worse performance than expected. The figures made 2012 the first full year since 1995 in which no quarter produced economic growth in the euro zone. "It's a small hiccup in Europe's longer-term growth picture ... but it does have a short-term impact on the TSX," said Victor Kuntzevitsky, an associate at Northland Wealth Management. The Toronto Stock Exchange's S&P/TSX composite index ended down 53.49 points, or 0.42 percent, at 12,721.79, its lowest closing level since Feb. 4. Seven of the 10 main sectors on the index were weaker. The energy sector lost 1.6 percent and played the biggest role in leading the market lower as oil price moves remained choppy. Oil producer Cenovus Energy Inc dropped 2.5 percent to C$31.79 after reporting a fourth-quarter operating loss, and saying it expects more pressure on costs this year due to higher power prices. In other individual company news, BlackBerry's former co-chief executive, Jim Balsillie, disclosed that he had sold his once-sizable stake in the embattled smartphone maker. Shares of BlackBerry, which launched its make-or-break BlackBerry 10 smartphone last month, initially slipped on the news before climbing 7.5 percent to C$15.05. "The stock is more of a speculation than an investment at this point," said Michael Sprung, president of Sprung Investment Management. "You're going to see huge volatility in BlackBerry until it becomes apparent one way or the other whether (BlackBerry 10) is a success or not." The index's materials sector, which includes mining stocks, gained 0.2 percent, benefiting from earnings results and higher gold prices. Barrick Gold reported a fourth-quarter loss after booking a $3.8 billion charge to write down the value of its copper mine in southern Africa. But shares of the world's biggest gold miner added 2.3 percent to C$32.44 as profit before special items beat market expectations. Another big gainer was Kinross Gold Corp, which on Wednesday reported higher fourth-quarter revenue. The stock jumped 5.4 percent to C$8.34. Of the more than 20 percent of TSX stocks that have reported earnings for the quarter, 62 percent have met or beat expectations, according to Thomson Reuters StarMine data.