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If the currency ends up for the week, it will be its longest winning streak since 1997.
Gold, on the other hand, logged its fourth straight daily loss.
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"A strong dollar environment is always going to put downward pressure upon commodity prices and it is especially wearisome for those who are bullish of gold," Gartman said.
However, he noted that when you look at gold in terms of the yen and the euro, "it's actually quite strong. Gold is nothing other than a currency."
He also thinks the move in U.S. crude Thursday was notable. It made a low in the morning after the "enormously bearish news" about the expectation of a more subdued demand growth in the oil markets. It later reversed to the upside.
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"That's very impressive. I pay attention to reversals such as we had in crude oil. That might have been an important low," Gartman said.
—By CNBC's Michelle Fox. Reuters contributed to this report.