(Adds portfolio manager quotes and details throughout; updates prices)
* TSX ends down 4.47 points, or 0.03 percent, at 15,802.70
* Index touches highest intraday since Feb. 23 at 15,866.82
* Five of TSX's 10 main industry groups end lower
* Materials group falls 0.7 percent
By Fergal Smith
TORONTO, Oct 16 (Reuters) - Canada's benchmark stock index edged lower on Monday, giving up its earlier gains, as profit-taking by investors in gold pressured shares of companies that mine the precious metal.
Gold, which had been boosted this month by tensions over Iran and North Korea, retreated 0.8 percent to $1,291.90 an ounce.
Barrick Gold Corp, the world's largest gold miner, fell 2.2 percent to C$20.35 and Agnico Eagle Mines Ltd retreated 2.3 percent to C$57.00.
In contrast, shares of copper producer First Quantum Minerals climbed 2.5 percent to C$15.84, after copper broke through the $7,000 a tonne mark for the first time in three years, buoyed by data from China.
The materials group, which includes precious and base metals miners and fertilizer companies, lost 0.7 percent.
Shares of Magna International Inc lost 2.8 percent to C$66.48. The stock has pulled back as much as 5 percent since posting a nearly 2-year high on Wednesday.
Auto parts makers, such as Magna, could be hurt if negotiators fail to reach a deal to renew the North American Free Trade Agreement.
The Trump administration has presented a series of hard-line proposals in the latest round of talks over NAFTA's modernization that partners Canada and Mexico say will be tough to accept.
"If you are a risk averse investor, you take a little off the table," said Rick Hutcheon, president and chief operating officer at RKH Investments.
The Toronto Stock Exchange's S&P/TSX composite index closed down 4.47 points, or 0.03 percent, at 15,802.70.
Still, it touched its highest intraday since Feb. 23 at 15,866.82 and has rallied 5.7 percent since early September.
"We have had such a good move, a little check back here wouldn't be surprising," Hutcheon said. "But I don't think it is going to be anything more than that."
Hutcheon expects upcoming quarterly earnings results to be robust, boosted by Canada's strong economic performance this year.
Canadian companies have seen capacity and labor market pressures intensify over the past year, the Bank of Canada said in its quarterly Business Outlook Survey.
The groups of financial and energy shares, which together account for 54 percent of the TSX's weight, each rose 0.1 percent.
U.S. crude oil futures settled 0.8 percent higher at $51.87 a barrel as Iraqi forces entered the oil-rich city of Kirkuk.
Shares in Hudson's Bay Co, which is reviewing strategic options including taking the company private, fell 4.6 percent to C$11.74, with some analysts attributing the drop to rival Nordstrom Inc's failed attempt to go private. (Additional reporting by Solarina Ho; Editing by Nick Zieminski and Tom Brown)