* TSX down 39.21 points, or 0.26 percent, to 14,985.32
* Index down 1.4 percent on the week
* Four of the TSX's 10 main groups are lower
TORONTO, Sept 8 (Reuters) - Canada's main stock index ended lower for a fifth straight day on Friday, with mining and energy stocks dominating the retreat and investors cautious as powerful Hurricane Irma barreled toward Florida.
Nine of the 10 biggest drags on the index were mining and oil and gas stocks.
Teck Resources Ltd sank 5.4 percent to C$28.23, while First Quantum Minerals Ltd fell 3.8 percent to C$13.76. Hudbay Minerals Inc plunged 10.2 percent to C$9.65 after the company announced a C$242 million bought deal financing.
Encana Corp was down 3.6 percent to C$11.20, while Cenovus Energy gave back 3.2 percent to C$9.85.
The Toronto Stock Exchange's S&P/TSX composite index finished down 39.21 points, or 0.26 percent, to 14,985.32. The index lost 1.4 percent on the week.
Six of the index's 10 key sectors rose, but energy stocks, which accounts for about a fifth of the index's weight, retreated 1.5 percent.
The overall materials group lost 1.2 percent.
"It was a little adjustment, because (materials have) been one of the best performing areas in Toronto when Toronto itself hasn't done very well at all," said John Kinsey, portfolio manager at Caldwell Securities.
Cuba began shutting down its nickel industry in preparation for Hurricane Irma, while copper prices fell on profit-taking as analysts said the recent price surge was not justified.
Oil and gas companies fell as U.S. crude prices tumbled more than 3 percent on worries that demand would be hit hard due to Hurricane Irma, one of the most powerful storms in a century.
The heavily weighted financials sector gained 0.1 percent after losing more than 2 percent in the last week.
"They've been real laggards for some time. The banks and insurance companies should do well with interest rates rising," said Kinsey.
Declining issues outnumbered advancing ones on the TSX by 171 to 73, for a 2.34-to-1 ratio on the downside.
The index posted five new 52-week highs and five new lows. (Reporting by Solarina Ho; Editing by James Dalgleish)