The US will impose a 50% tariff on imported copper pipes, tubes, and wiring, effective this Friday (August 1). Secretary of Commerce Howard Lutnick had said that such imports pose a national security threat.

The tariff, narrower than initially expected, excludes raw copper materials such as ores, concentrates, and cathodes.

This new tariff, specifically focusing on semi-finished copper products and products that heavily use copper, caused US copper prices on the Comex exchange to decline by over 17%, erasing a recent premium over London global benchmarks.

The policy is to support domestic manufacturers, but it offers little direct benefit to the US copper mining industry. Major copper producers Chile and Peru, main suppliers to the US, are likely to see a boost from the exclusion of raw copper.