The materials group, which includes precious and base metals miners as well as fertilizer companies, lost 1.1 percent as a pullback in the price of safe-haven bullion weighed on gold miners.

Spot gold dipped more than 1 percent after Federal Reserve Chair Janet Yellen said the U.S. central bank needed to continue gradual interest rate hikes, despite weak inflation. [GOL/]

Agnico Eagle Mines Ltd finished down 3.4 percent at C$56.78, while Barrick Gold Corp fell 1.3 percent at C$20.28.

Copper prices also declined, ending the session down 0.6 percent to $6,411 a tonne after touching its lowest since mid-August on Friday. [MET/L]

The Toronto Stock Exchange's S&P/TSX composite index ended 42.11 points, or 0.27 percent lower, to 15,474.12.

The index had posted its highest close since May 16 at 15,516.23 on Monday.

Industrials, home to Bombardier Inc, was the only group that rose among the TSX 10 biggest sectors.

Energy issues, which have rallied some 13 percent since late August, declined 0.3 percent on the back of softer oil prices, though individual stock moves were more moderate.

Investors were taking profits after prices of crude rallied to a 26-month high in the previous session, fueled by threats from Turkey to cut crude exports from Iraq's Kurdistan region.

U.S. crude futures settled at $51.88 a barrel, down 0.7 percent. [O/R]

"This is a group where everybody gets hot and cold about and it looks like they're getting hot about it coming into the fall - today not withstanding," said John Ing, president of Maison Placements Canada. "There's hopes of a production cut-back continuation and demand remains strong."

Bombardier Inc shares reversed course sharply during the session, jumping as much as 13.6 percent in afternoon trading, ahead of a U.S. trade court's preliminary ruling on Boeing Co's aircraft dumping complaint. The stock closed up 6.1 percent at C$2.27.

The court decision over whether Bombardier is dumping its new CSeries passenger jet in the U.S. aircraft market was expected to be made public on Tuesday.

The planemaker also aims to close deals with Chinese airlines in time for an expected trip by Canadian Prime Minister Justin Trudeau to China next month, a senior Bombardier executive said.

The financials group, which accounts for more than one third of the index's weight, dipped 0.2 percent. Healthcare stocks were off 0.5 percent.

(Reporting by Fergal Smith and Solarina Ho; Editing by W Simon and James Dalgleish)

By Solarina Ho