Traders worried about escalating tensions between Ukraine and Russia have turned to 10-year Treasury notes as their main indicator of fear in the markets, veteran trader Art Cashin told CNBC on Monday.
Given the triple-point gains in Monday's morning trading session, Wall Street doesn't seem all that afraid. Stocks moved in lockstep with benchmark 10-year Treasury notes during Monday's trading session, rising 100 points when yields reached session highs and edging lower when yields dropped, said Cashin, UBS' director of floor operations at the NYSE.
Stocks bounced back when yields returned near session highs, he said.
Treasurys measure fear better than the CBOE Volatility Index, and traders look to them to parse through news headlines, Cashin said. Yields reached highs of 2.66 percent Monday.
"If there's troop movements or real hostility, the first place they'll see that is in the 10-year," Cashin said on "Squawk on the Street," adding: "Everybody talks about the VIX, but the new fear gauge is in fact the 10-year. If you took this morning apart minute by minute, you would see that stocks have reacted exactly with the 10-year."
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Cashin called the VIX, which measures volatility in the market, a "broken indicator." He added that investors should monitor resistance levels of 1,838 and 1,841 for the during Monday's trading.
—By CNBC's Jeff Morganteen.