Copper jumps to its highest level ever. What the metal is telling us

Copper surged to a record high Thursday, but the latest rally comes against a more mixed growth backdrop, making the once-reliable gauge of economic health, "Dr. Copper," harder to read.

U.S. copper futures climbed to around $6.90 a pound Thursday, extending a rally in a metal used for construction, electronics, transportation and even AI applications. It then retreated to end the session after touching the new high.

But instead of simply indicating stronger global growth, today's record price could be reflecting a combination of constrained supply, heavy grid investment, uncertainty around U.S. tariffs and rising demand for electrification.

In the past, the metal was seen as a gauge on whether global economic activity was ramping up.

"The underpinning story of elevated copper prices has been data center and power grid demand to support the rapid AI industry expansion," William Osnato, Barchart director of commodity data research and analysis, told CNBC in an email, adding that surge in copper demand is "more acute and not the traditional broad economic growth that supports copper."

Copper's price surge is also due to its limited supply and mining it is an expensive business and setting up new mines can take about 10 years, which can also slow down supply of the red metal.

Michael Widmer, Bank of America's head of metals research told CNBC that the move wasn't really driven by copper demand but really driven by copper supply.

Widmer said there is not a lot of mine supply growth and supply disruptions have been creating additional constraints. Mine growth has been weak, with disruptions in Chile , the world's biggest single copper producer. Heavy snow, rainfall and high winds have disrupted mining operations in the region.