(Updates throughout with closing prices) TORONTO, Feb 9 (Reuters) - Canada's main stock index fell on Friday, closing at its lowest level in five months, reflecting weakness in mining stocks as gold futures and copper prices declined. * The Toronto Stock Exchange's S&P/TSX composite index closed down 31.08 points, or 0.21 percent, to 15,034.53. * Of the index's 10 main industry groups, seven ended in negative territory. * The materials group, which includes precious and base metals miners and fertilizer companies, lost 1.1 percent. * Guyana Gold slid by 7.6 percent, Eldorado Gold shed 7.1 percent, New Gold dropped by 6.3 percent and Oceangold Corp was down 5.9 percent. * The largest percentage decliner was Sierra Wireless Inc , down 13.6 percent, after the company reported a fourth-quarter loss after the bell on Thursday. * U.S. gold futures settled down 0.3 percent at $1,315.70 an ounce. * Copper prices declined 1.4 percent to $6,750 a tonne. * The index was posting no new 52-week highs and 50 new lows. * The Canadian economy lost the most jobs in nine years in January, pulling back after a robust 2017 and solidifying expectations the Bank of Canada will hold interest rates steady next month . (Reporting by Fergal Smith, editing by G Crosse)