Canada's main stock index retreated from a record high on Thursday, as major gold miners weighed the most while energy shares were pulled down by concerns over slow demand recovery in the global crude market.

At 9:43 a.m. ET (13:43 GMT), the Toronto Stock Exchange's S&P/TSX composite index was down 99.22 points, or 0.48%, at 20,454.79.

The materials sector, which includes precious and base metals miners and fertilizer companies, lost 1.1% as gold prices retreated from recent gains made on signs of slowing US consumer inflation.

The energy sector dipped 0.2% as oil prices were dented by a warning from the International Energy Agency that the Delta variant of the coronavirus could hurt fuel demand.

TSX hovers near record high as gold prices boost miners

The financials sector slipped 0.4%. The industrials sector fell 0.2%.

On the TSX, 79 issues were higher, while 146 issues declined for a 1.85-to-1 ratio to the downside, with 12.94 million shares traded.

The largest percentage gainer on the TSX was Ats Automation Tooling Systems, which jumped 5.7% to extend gains into a second session after the company posted bumper quarterly results.

Northland Power fell 7.5%, the most on the TSX, after its revenue missed estimates. The second-biggest decliner was Endeavour Silver, down 5.8%, tracking weakness in precious metals.

The most heavily traded shares by volume were Bombardier B , Well Health Technologies, and Nevada Copper .

The TSX posted 18 new 52-week highs and three new lows.

Across all Canadian issues, there were 72 new 52-week highs and 9 new lows, with total volume of 28.48 million shares.