July 18 (Reuters) - Canada's main stock index fell on Thursday as the materials sector slid tracking lower gold prices, while investors waited for the latest developments on the U.S.-China trade dispute.
* Gold prices fell as investors booked profits after the metal hit a two-week high on increased expectations of a dovish monetary policy stance from the U.S. Federal Reserve. GOL/
* At 9:46 a.m. ET (13:46 GMT), the Toronto Stock Exchange's S&P/TSX composite index .GSPTSE was down 7.3 points, or 0.04%, at 16,476.91.
* U.S. and Chinese officials will hold a telephone call later on Thursday that could pave the way for further in-person trade talks, U.S. Treasury Secretary Steven Mnuchin told CNBC.
* Global stocks were rattled after U.S. President Donald Trump on Tuesday reiterated his threat to impose further tariffs on Chinese imports.
* Healthcare companies .GSPTTHC slid 0.88%, the most among the major sectors trading lower, and the materials sector .GSPTTMT , which includes precious and base metals miners and fertilizer companies, lost 0.5%
* The energy sector .SPTTEN dropped 0.4% as U.S. crude CLc1 prices were down 0.3% a barrel, while Brent crude LCOc1 lost 0.2%. O/R
* On the TSX, 81 issues were higher, while 145 issues declined for a 1.79-to-1 ratio to the downside, with 13.33 million shares traded.
* The largest percentage gainer was Air Canada AC.TO , up 3.9%. Brokerage CIBC raised its price target on the carrier.
* Alaris Royalty AD.TO followed with a 1.5% rise.
* Vermilion Energy VET.TO fell 3.4%, the most on the TSX, after RBC downgraded its shares to "sector perform" from "outperform"
* The second biggest decliner was Alacer Gold Corp ASR.TO , down 3.4%.
* The most heavily traded shares by volume were New Gold NGD.TO , Aurora Cannabis ACB.TO and B2gold Corp BTO.TO .
* The TSX posted 14 new 52-week highs and five new lows.
* Across all Canadian issues there were 33 new 52-week highs and 15 new lows, with total volume of 25.68 million shares.