The Toronto Stock Exchange's TSX falls 0.12 percent to 17,490.56
Leading the index were OceanaGold Corp , up 12.4%, Real Matters Inc , up 3.6%, and Celestica Inc , higher by 2.9%.
Lagging shares were Silvercorp Metals Inc , down 6.8%, Shawcor Ltd, down 6.3%, and Methanex Corp, lower by 5.1%.
On the TSX 81 issues rose and 148 fell as a 0.5-to-1 ratio favored decliners. There were 14 new highs and 5 new lows, with total volume of 186.3 million shares.
The most heavily traded shares by volume were Detour Gold Corp , First Quantum Minerals Ltd and Canadian Natural Resources Ltd.
The TSX's energy group fell 0.25 points, or 0.2%, while the financials sector slipped 0.73 points, or 0.2%.
West Texas Intermediate crude futures fell 0.98%, or $0.52, to $52.82 a barrel. Brent crude fell 1.25% , or $0.75, to $59.06 [O/R]
The TSX is up 2.5% for the year.