Canada's main stock index slipped on Tuesday, as banks pulled back at the end of their earnings season and one warned about mortgage originations while mining stocks also weighed with copper and gold prices hitting two-month lows.

The Toronto Stock Exchange's S&P/TSX composite index ended down 53.35 points, or 0.33 per cent, to 15,915.68. Seven of its 10 main groups finished lower while decliners were outnumbering advancers by almost 2-to-1.

The heavyweight financials group slipped 0.5 per cent, with Toronto-Dominion Bank (TD.TO) off 1.3 per cent at $72.43.

Shares in smaller lender Laurentian Bank of Canada (LB.TO) fell 7.9 per cent to $56. The bank said in an annual report that it had identified documentation issues and client misrepresentations in some mortgages at its B2B Bank subsidiary and plans to perform an in-depth review of originations.

The materials group, which includes precious and base metals miners and fertilizer companies, lost one per cent as miners of copper, nickel, zinc and other base metals were hit hard by falling commodity prices.

First Quantum Minerals Ltd (FM.TO) fell 4.5 per cent to $14.56 and Teck Resources Ltd (TECKb.TO) lost 2.9 per cent to $28.99 as copper prices fell their most in two years to hit a two-month low.

Gold miners also fell, with Goldcorp Inc (G.TO) shedding 2.2 per cent to $15.61 and Barrick Gold Corp (ABX.TO) off 0.9 per cent at $17.51 as gold dropped one per cent to a two-month low.

Commodity prices were in part hurt by a stronger U.S. dollar on the back of a U.S. tax overhaul plan.

Licensed marijuana producer Aphria Inc (APH.TO) jumped 16.4 per cent to $13.53 after saying it had reached a deal to supply medical cannabis to Loblaw Cos Ltd's (L.TO) pharmacy chain Shoppers Drug Mart.

Bombardier Inc (BBDb.TO) ended one per cent higher at $3.17 after two sources said Aeromexico has held preliminary talks to take some of its CSeries jets orders from Delta Air Lines Inc, which owns a stake in the Mexican carrier, to avoid possible U.S. trade duties levied on the planes.

The heavyweight energy group was little changed, while Kinder Morgan Canada Ltd (KML.TO) fell 2.6 per cent to $16.61 after saying late on Monday that the start-up of its Trans Mountain pipeline expansion could be delayed past September 2020.