Gartman: This chart says risk on

Gartman: This chart says risk on

There are traders, and then there is Dennis Gartman, or as The Street calls him, The Commodities King.

Gartman became Wall Street royalty chiefly by recognizing risk and making smart, opportunistic bets. But despite what his moniker may suggest, Gartman has made money trading not only things like oil and gold, but also equities and currencies.

(Read: Gold edges lower on caution over US policy outlook)

So what does he look to inform his trades? What inputs does he use to fashion his investment thesis?

Curiously enough, when gauging risk, Gartman doesn't look solely to the commodities market. Instead, he looks to the currency market, or more accurately, currency pairs that track the performance of commodities.

"The world needs commodities and so they will be coming to those currencies," said Gartman.

(Read: Brent stays above $109 on upbeat China PMI data)

Specifically, he looks to the Aussie and Canadian dollars to gauge commodity demand. When demand is high, those currencies will rally, particularly against the yen. To Gartman, this is a sign that risk is "on" and investors should consider moving into things like oil and stocks.

So what chart could be flashing a buy sign for stocks? Click the video above and find out.

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