(Adds strategist's comment, updates prices to close)
* TSX ends down 57.66 points, or 0.40 percent, at 14,193.87
* Nine of 10 main sectors fall
By Alastair Sharp
TORONTO, Aug 18 (Reuters) - Canada's main stock index fell on Tuesday, its seventh decline in the last nine sessions, with miners and railways leading a broad retreat as copper hit a six-year low and Chinese equities tumbled.
First Quantum Minerals Ltd plunged 9.7 percent to C$7.65 and Teck Resources Ltd shed 8 percent to C$8.39.
"The rally that we saw in late July has pretty much been snuffed out," said Elvis Picardo, a strategist at Global Securities in Vancouver. "And it looks like the TSX is inexorably on track to test the 14,000 support level again."
The Toronto Stock Exchange's S&P/TSX composite index lost 57.66 points, or 0.40 percent, to end at 14,193.87. Nine of its 10 main sectors fell.
Declining issues outnumbered advancers by 147 to 92, for a 1.60-to-1 ratio on the downside, while the index posted three new 52-week highs and 21 new 52-week lows.
Telecoms were the only group to gain, which Picardo ascribed to investors seeking out their attractive yields while worrying about the sustainability of energy sector dividends.
Other influential decliners included pipeline operator Enbridge Inc, which fell 1.2 percent to C$55.22, and Barrick Gold Corp, which sank 3.2 percent to C$8.39.
Canadian National Railway Co slipped 0.8 percent to C$79.51 and Canadian Pacific Railway Ltd lost 1.5 percent to C$202.68, emblematic of concerns about Canada's economic health.
"The continuation of a sell-off for all commodities is something that's also lingered on," said Bryden Teich, associate portfolio manager at Avenue Investment Management. "It's a period of pain for a lot of the commodity industries and producers."
Energy shares on the Toronto stock market have been hit particularly hard this year with oil prices dropping to near 6-1/2-year lows. Teich said there is still too much global crude supply and it is impossible to say when oil prices may bottom.
Investors are waiting to see if the minutes from the U.S. Federal Reserve's last policy meeting, due to be released on Wednesday, provide clues on when it might start raising interest rates, a move that some see coming as early next month.
"It's definitely come to the point where they need to at least raise rates away from crisis-level interest rates," Teich said. "It signals confidence in the economy."
$1=$1.31 Canadian Additional reporting by Solarina Ho; Editing by Peter Galloway and Paul Simao