* TSX down 45.02 points, or 0.34 percent, at 13,338.67
* Eight of the TSX’s 10 main groups end lower
TORONTO, Sept 24 (Reuters) - Canada’s main stock index slipped on Thursday as worries about global economic growth weighed on most major sectors, offsetting a gain in shares of mining companies.
The drop extended the benchmark index’s losses for a third straight session. The TSX is down about 9 percent since the start of the year.
The TSX, which is sensitive to commodity prices due to its high concentration of resource names, has been particularly volatile over the last month amid growing worries that slowing global growth will hurt demand in those sectors.
“We see further weakness in the equity markets in the medium term,” said Youssef Zohny, portfolio manager at StennerZohny Investment Partners of Richardson GMP Ltd, which manages about C$28.3 billion in assets.
“But there are pockets of opportunity, and we saw that today with the big rally in gold,” he added.
The Toronto Stock Exchange’s S&P/TSX composite index closed down 45.02 points, or 0.34 percent, at 13,338.67. Eight of the 10 main sectors on the index were in the red.
Financial shares were down 0.5 percent. Bank of Montreal fell 0.2 percent to C$69.79, and Bank of Nova Scotia lost 0.5 percent to C$57.24.
The materials sector, home to resource firms, climbed 3.6 percent on the back of rallying gold mining stocks. The price of gold rose to a three-week high after the U.S. dollar softened on soft economic data.
Goldcorp Inc jumped 7.4 percent to C$17.97, while Barrick Gold Corp surged 10.4 percent to C$8.72.
Valeant Pharmaceutical International had the biggest negative pull on the in TSX, falling 3.8 percent to C$278.69. Healthcare retreated 3.1 percent. (Reporting by Solarina Ho and John Tilak; Editing by Meredith Mazzilli and Phil Berlowitz)