(Updates prices, adds analyst comments) Oct 29 (Reuters) - Canada’s main stock index retreated on Friday, a day after posting its best session in five months, as miners and energy stocks slipped due to weaker commodity prices. At 9:49 a.m. ET (13:49 GMT), the Toronto Stock Exchange’s S&P/TSX composite index was down 93.43 points, or 0.44%, at 21,104.1 and was on track to snap its three-week winning streak. The materials sector, which includes precious and base metals miners and fertilizer companies, lost 1.4% as gold futures fell 1.4% to $1,777 an ounce. Eldorado Gold down 8.2%, led declines on the sub-sector index and was the biggest drag on the index after posting a dismal third quarter earnings. The energy sector fell 0.7% on the back of weaker oil prices, and a 6.7% slide by Imperial Oil Ltd despite posting its third-quarter profit, which more than doubled from the prior quarter. “This week was just the tip of the iceberg for Canadian earnings and it’s really next week. So I think what we are seeing in today’s market is a bit of setup for next week as investors position themselves for the rest of earnings,” said Colin Cieszynski, chief market strategist, SIA Wealth Management. After snapping its seven-month winning streak in September, the Canadian equity index was on track to end October in gains helped by stronger commodities and on prospects of corporate earnings. Adding further losses were Toronto listed technology stocks , which fell 0.7% tracking weakness in tech-heavy Nasdaq index. Meanwhile official data showed that the Canadian economy most likely experienced zero growth in September, following a 0.4% gain in August, prompting analysts to forecast the Bank of Canada might raise interest rates more slowly than expected. HIGHLIGHTS The TSX posted six new 52-week highs and no new lows. Across all Canadian issues, there were 22 new 52-week highs and eight new lows, with total volume of 42.32 million shares. (Reporting by Amal S in Bengaluru; Editing by Shinjini Ganguli)