The Standard & Poor's/TSX composite index closed up 2.28 points, or 0.2 percent, at 12,816.42. In earlier trading it plunged 250 points, or 2 percent.

The benchmark index lost 955 points, or nearly 7 percent, since Tuesday. The trading week was shortened because of the Labor Day holiday Monday.

The TSX Venture Exchange, based in Calgary, Alberta, fell 17.32 points, or 0.95 percent, to close at 1,812.11.

The Canadian dollar was up 0.55 cent to 94.05 U.S. cents.