Futures Now

The metal that's worried about global growth

An employee scans barcodes on copper rods as they sit stacked outside at the Aurubis AG headquarters in Hamburg, Germany.
Krisztian Bosci | Bloomberg | Getty Images

Copper futures slid more than 1 percent Wednesday, falling to the lowest level since late June as investors looked at an increasingly dour picture for global growth.

According to data released Wednesday, China's industrial production rose 9 percent in July, and its retail sales rose 12.2 percent. Both numbers missed expectations. And in more bad Chinese news, new loans for July fell nearly 70 percent from June.

Read More Weak China July money data cast doubts on recovery

In reaction to the disappointments, the industrial metal copper—which is used in everything from factory equipment to new buildings–dropped sharply overnight, hitting the lowest level since June 20.

"It's pretty much the Chinese data that really sank the copper market, and the business with new loans," said Edward Meir, a metals analyst with INTL FCStone. "All these Chinese stimulus measures really fell short when it came to changing the psychology."

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Copper has traditionally been thought of as an indicator of the global economy. In fact, some refer to it as "Dr. Copper" for its propensity to check-up on the "health" of other risk assets, including U.S. equities. And it hasn't been the only industrial commodity dropping recently—Brent crude oil hit a 13-month low Wednesday.

Copper "still is reflective of a very uneven, mixed, mediocre global economy," said Peter Boockvar, chief market analyst at the Lindsey Group. "While the U.S. economy is improving and the labor market is improving, it's still very much a mixed bag."

So where does it go from here?

Meir sees it staying in its trading range, rather than rebounding anytime soon.

"It's not going to be the leader in the metals group like it used to be," he said.

—By CNBC's Alex Rosenberg

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