By Bloomberg News

(Bloomberg) — Mining giant Rio Tinto Group (RIO.L) said US tariffs on its Canada-made aluminum generated gross costs of more than $300 million in the first half, in another sign of how President Donald Trump’s trade agenda is shaking up metals supply chains.

Most Read from Bloomberg

• The Dutch Intersection Is Coming to Save Your Life

• Advocates Fear US Agents Are Using ‘Wellness Checks’ on Children as a Prelude to Arrests

The world’s second-biggest miner is also Canada’s largest aluminum producer, and sells the vast bulk of the metal in the US. Rio said Wednesday it incurred gross costs of $321 million associated with US tariffs on aluminum, but added that a “substantial part” has been clawed back from higher premiums on US sales.

Metals industries are adjusting to the trade tumult unleashed by Trump this year. He slapped blanket 25% import fees on steel and aluminum in March, before raising those to 50% in June. A planned 50% tariff on copper triggered market mayhem, and the administration is probing potential measures on other metals.

Rio said premiums in the US market — paid on top of exchange prices — rapidly adapted to the initial 25% tariff, but were not fully compensating for the 50% level by the end of the second quarter. The company shipped about 723,000 tons of aluminum to the US in the first half — equivalent to about three-quarters of its output from Canada.

Futures tracking aluminum prices in the US have pointed to higher costs for American buyers, and industry executives have warned the tariffs risk crushing American demand. Earlier this month, beverage maker Constellation Brands Inc. said it expects aluminum tariffs to cost the company about $20 million over the remainder of its fiscal year.

Contracts linked to the premium on the metal delivered to the Midwest have almost tripled this year to reach a record near 66 cents a pound.

“The impact of tariffs is still feeding through to inflation and sentiment,” Rio said in an overview of the US economy in its first-half production report.

—With assistance from Paul-Alain Hunt.

(Updates with details from fifth paragraph)

Most Read from Bloomberg Businessweek

• Forget DOGE. Musk Is Suddenly All In on AI

• How Starbucks Is Engineering a Turnaround With Warm Vibes and Cold Foams

• How Hims Became the King of Knockoff Weight-Loss Drugs

• Thailand’s Changing Cannabis Rules Leave Farmers in a Tough Spot