TORONTO (Bloomberg) — Canada's main stock index fell for the first time in seven days, led by mining and energy stocks including Suncor Energy Inc. and Teck Cominco Ltd., as gold and oil prices dropped.Research In Motion Ltd. rose on prospects of higher earnings.

"A one-day decline in resource prices doesn't help the Canadian market," said Michael Smedley, who helps manage about $1 billion at Morgan Meighen & Associates in Toronto. "Resources occupy 45 percent of the market and our country has roughly 50 percent of the world's unrestricted oil and gas reserves."

The Standard & Poor's TSX Composite Index dropped 196.24, or 1.4 percent, to 13,946.27 in Toronto. It was the biggest drop since April 30.

Teck Cominco, a zinc and copper miner, fell C$1.72, or 4 percent, to C$41.68. The stock was cut to "sector perform" from "outperform" by analyst Fraser Phillips at RBC Capital Markets after Teck Cominco said yesterday it joined NovaGold Resources Inc. in a joint venture that will spend $2 billion to develop the Galore Creek copper and gold mine in British Columbia.

Gold shares fell after the spot price of the metal dropped $8.76 to $653.17 an ounce. The price is heading for the third straight weekly decline. Copper also fell, dropping 3.5 percent to a seven week-low on concern that inventories in China will rise.

Goldcorp Inc., the world's third-biggest gold producer, dropped 87 cents, or 3.5 percent, to C$24.37. Barrick Gold Corp., the biggest producer, dropped 77 cents, or 2.4 percent, to C$31.44. NovaGold fell 79 cents, or 4.8 percent, to C$15.58.

Suncor, the second-biggest oil-sands producer, fell C$2.50, or 2.6 percent, to C$92.80. EnCana Corp., the country's biggest gas producer, fell C$1.36 cents, or 2 percent, to C$65.15.

Crude oil prices plunged $1.59, or 2.4 percent, to $64.18 a barrel on the New York Mercantile Exchange, the biggest one-day decline since April 1.

An index of information technology stocks rose 0.5 percent, the only industry group that gained, as Research In Motion advanced.