TORONTO (Reuters) - Toronto's main stock index ended lower yesterday after touching a two-year high earlier in the session, as a steep rise by the US dollar helped push commodity prices lower.

Spot gold soared to a record high for a fourth day running, touching above $1,424 an ounce, but retreated sharply by day's end as the stronger greenback prompted heavy profit-taking by investors.

Barrick Gold sank 0.5 percent to C$51.25, while Yamana Gold dropped two percent to C$11.69, helping the TSX's gold subgroup slide 2.7 percent. The broader materials sector, home to miners and fertilizer companies, was down 2.4 percent.

"The market has really been focused the past few days on the metals side of things, particularly as gold made all-time highs again today," said Aaron Fennell, senior market strategist at Lind-Waldock Canada. "But today, it dramatically turned around from that and I think there is a change in perspective."

The precious metal sank on a firm US currency, which rose in part after being beaten down ahead of the Federal Reserve's decision to pump more money into the struggling US economy, said Mr. Fennell.

Analysts also said the greenback got a lift as investors unwound US dollar short positions, while investors flocked to the safety of the greenback on concerns about euro zone debt. The Toronto Stock Exchange's S&P/TSX composite index finished down 135.85 points, or 1.04 percent, at 12,916.63, snapping three days of gains. Earlier, the index hugged 13,114.05, its strongest level since September 8, 2008.

Financials were also a key drag on the broader market, falling 1 percent. Toronto-Dominion Bank was off 1.3 percent at C$73.65, while Royal Bank of Canada shed 1.5 percent to C$54.40.