It's been a bad year for gold, but one widely followed commodities watcher says the bottom is in.

"So after a 4½ year bear market, it's time to be bullish," Dennis Gartman told "Fast Money" traders Monday. "I got longer of gold late last week, and if we get above 1,085 I will get longer."

Gold settled at its highest level in two weeks on Monday, rising more than 1 percent to $1080.60 an ounce, but it isn't gold's move higher that has the commodities king intrigued.

"What really had my interest was the CFTC reports that came out last week indicating that the commercials, as they're called, who are normally enormously net short, are almost net long," the editor of the Gartman Letter said. "The fact that commercials are effectively net long and the public is abundantly out — that is a reason to be abundantly in."

According to Gartman, in the "enormously rare" instances that commercial interests shift their participation to the long side, its an indication that "real" bull markets have begun.

Gold commercial interests can be described as miners, refiners or jewelers with gold inventory on hand.

"Commercials are always ahead of the public," said Gartman. "The last time we saw this happen in the other direction was when the commercials got egregiously net short back in November of 2011. They're the ones that call the top, they're the ones that call the bottom, so that alone has me interested."

The commodity has fallen more than 40 percent since November 2011.