By Rhiannon Hoyle

Iron-ore shipments from Rio Tinto's massive Australian mining operations are likely to fall at the lower end of the miner's estimates this year, following disruptions from four cyclones in recent months.

The miner, which generates the bulk of its profits by extracting the steelmaking ingredient in Australia's remote Pilbara region, said Wednesday that it shipped 70.7 million metric tons of iron ore from those operations in the three months through March.

That figure is 9% lower than the same period a year earlier and 17% below the immediately preceding quarter. It marks the company's weakest first-quarter shipment result since 2019.

Rio Tinto, the world's second-largest miner by market value, has been grappling with disruptions and damage from cyclones that lashed northwest Australia in the early months of 2025.

The company recently estimated it lost about 13 million tons in shipments due to tropical cyclones Tahlia, Vince, Zelia and Sean.

On Wednesday, it said it still expects to ship between 323 million and 338 million tons this year, as previously forecast to investors in December. However, it said that exports may end up at the lower end of that range due to those losses.

The first-quarter result disappointed analysts, who had expected shipments of roughly 73.3 million tons, according to a consensus estimate compiled by Visible Alpha. Shares in the company were down 1.7% by midday in Sydney.

Rio Tinto reported an on-year increase in first-quarter output of copper, alumina and bauxite, and said aluminum production was little changed.

The miner has been expanding its copper operations, betting that the industrial metal will be crucial for the global shift to clean energy. It also recently acquired Arcadium Lithium, making the company one of the world's largest producers of lithium, a key battery material.

Rio Tinto said there was limited impact on its commodities from new tariffs in the first quarter, as President Trump imposed levies on steel and aluminum imports.

"However, there is an uncertain future impact from tariffs on the commodity markets going forward," the company said.

Rio Tinto is the largest shipper of foreign aluminum into the U.S., primarily from smelters it operates in neighboring Canada. The company has previously stated it has contingency plans to sell aluminum into other markets, such as Europe, if necessary.

On Wednesday, it said it expects U.S. economic activity may be affected by the tariffs, and noted that trade flows in borates--used in fertilizers, batteries and smartphone screens, among other things--are "already adjusting in response to tariffs enacted in the U.S. and China."

Rio Tinto's boron operations in California meet roughly 30% of global demand for refined borates, according to the company.

Write to Rhiannon Hoyle at rhiannon.hoyle@wsj.com

(END) Dow Jones Newswires

April 15, 2025 22:38 ET (02:38 GMT)

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