* TSX down 180.80 points at 10,388.49
* Energy and gold shares lead drop
* Slide follows 1.9 pct gain last week (Adds details and comments)
By Frank Pingue
TORONTO, June 8 (Reuters) - Toronto's main stock market index fell sharply on Monday morning, relinquishing a chunk of last week's gain, as a stronger U.S. dollar shook commodity prices and weighed on key energy and gold shares.
Oil prices fell further from last week's seven-month high above $70 a barrel and yanked the index's energy sector down by 1.8 percent. Oil companies were among the main drags on the TSX index.
A firmer U.S. dollar makes commodities such as oil, which is denominated in the currency, look more expensive to holders of other currencies.
"The U.S. dollar has been stronger in the last few trading days and so your commodities are all getting hit," said Sal Masionis, stockbroker at Brant Securities. "But that's normal since we had a good rally in commodities like oil and gold."
The index's materials group, home to gold-mining shares, led all sectors lower with a 3 percent skid as gold prices fell.
At 9:50 a.m. (1350 GMT), the S&P/TSX composite index .GSPTSE was down 180.80 points, or 1.71 percent, at 10,388.49. It rose 1.9 percent last week for its third straight week of gains.
$1=$1.12 Canadian Reporting by Frank Pingue; editing by Peter Galloway