The Liberian-flagged bulk carrier Nord Norfolk is sailing toward New Orleans carrying roughly $500 million of African copper, the highest market value for a single commodity shipment ever recorded by analytics firm Kpler. It is part of a rush of copper to US shores ahead of potential import tariffs under President Donald Trump, creating a logjam at the Port of New Orleans — a key hub for CME Group's Comex copper warehouses — which is already largely full. An additional 100,000 metric tons of African and South American copper is due in September and October.

"We are seeing serious congestion at marine terminals in the New Orleans area, causing delays for loading copper and other metals and steel to trucks and railcars," said Anton Posner, CEO of logistics-services provider Mercury Resources. His firm is sending metal up the Mississippi by barge instead. The arbitrage gap between US and international prices has narrowed to $169 a ton from a peak of $789, weakening the incentive to keep shipping to the US.

Warehousing companies are seeking approval for additional capacity from Comex. Since the start of 2025, the exchange has added 20 warehouses and nearly 725,000 short tons of copper capacity, equivalent to about 39% of annual US refined-copper consumption. Sites were added in Mobile, Chicago and Atlanta. Ryan Mc Kay, senior commodity strategist at TD Securities, said the White House will likely continue to delay a tariff decision to sustain domestic premiums.