Canada's main stock index edged lower on Monday as data showing a slowdown in the housing market weighed on the outlook for financials, offsetting gains for the materials group as metal prices climbed.

The resale of Canadian homes fell 6.7 per cent in June from May, the largest monthly drop since 2010 and the third straight monthly decline.

"A slowdown in real estate is somewhat of a negative for the banks," said Lorne Steinberg, president, Lorne Steinberg Wealth Management Inc. "Mortgage origination, consumer loans - all of that has been a huge boost for the Canadian banking sector."

Toronto-Dominion Bank fell 0.5 per cent to $64.86, while commercial real estate services company Colliers International Group Inc slumped 7.7 per cent to $70.29. The overall financial services group ended down 0.3 per cent.

Investors worry that higher interest rates will add to a slowdown in Canada's real estate market and weigh on the country's economy.

"A stronger Canadian dollar as well is somewhat of a negative for the Canadian economy and for Canadian exporters," Steinberg added.

The loonie touched its strongest level in 14 months at $1.2627 per U.S. dollar after the Bank of Canada last week raised interest rates for the first time in seven years.

Industrials fell 0.7 per cent, including losses for railroad stocks. Canadian Pacific Railway Ltd, which will release earnings on Wednesday, fell 1.2 per cent to $208.30.

The Toronto Stock Exchange's S&P/TSX composite index closed down 9.45 points, or 0.06 per cent, at 15,165.36.

Six of the index's 10 main industry groups ended lower.

The materials group, which includes precious and base metals miners and fertilizer companies, added 1.5 per cent. First Quantum Minerals Ltd jumped 8.8 per cent to $13.69 and Lundin Mining Corp advanced 4.9 per cent to $8.29.

Both miners produce copper, nickel and zinc. Copper prices reached their highest level since early March on the back of better-than-expected economic data from top consumer China, while nickel and zinc also gained.

Gold miners also rose as the price of the precious metal climbed.

Dominion Diamond Corp rose 5.6 per cent to $17.85, after the world's third-largest diamond producer by market value agreed to a sweetened takeover offer from The Washington Companies, valuing it at US$1.2 billion.

NexGen Energy Ltd rose 7.4 per cent to $3.18. But the energy group was little changed overall as oil prices fell.

U.S. crude futures settled 52 cents US lower at US$46.02 a barrel.