Major iron ore miners charted collective production growth in the first quarter, thanks largely to a spike in Rio Tinto Group's output, according to S&P Global Market Intelligence data.

Rio Tinto produced 69.8 million metric tons from its West Australian operations in the March quarter, up 7.3 MMt or 11.7% year over year, even though prices were sharply higher last year, when Russia's war in Ukraine triggered supply concerns.

The 20 companies surveyed reported an overall production of 315.8 MMt, which rose 9.8 MMt or 3.2% from the first quarter of 2022.

Rio Tinto's strong quarter was "unfortunately ... into a weakening market," said Jason Fairclough, head of Europe, the Middle East and Africa metals and mining for Bank of America Global Research, during a Q&A panel alongside Rio Tinto CEO Jakob Stausholm at the bank's May 16 conference in Barcelona, Spain.

Stausholm pushed back on Fairclough's assessment, pointing to Rio Tinto's $125/t average iron ore price in the first quarter, "which is a good market." Further, Rio Tinto's production "was needed by the market. So I have less concern on that front at this point in time."

"We will of course never produce more than what the market needs, but right now, we have stepped up, and there has been a demand for it," Stausholm said.

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Thirteen of the 20 companies analyzed managed to raise production year over year, although only eight increased output from the previous quarter. Ferrexpo PLC's production fell the most on a percentage basis at 64.8% year over year, and Brazil's Usinas Siderúrgicas de Minas Gerais SA had the biggest quarterly reduction at 21.4%.

Market sentiment in the first quarter see-sawed from a January price spike, which was triggered by optimism on demand from China, to easing prices on a buildup of steel stocks in February.

The S&P Global Platts IODEX 62% iron ore price then hit a nine-month high of $133.10/t on March 15 from "a combination of improved sentiment, increased steel output and restocking activity in anticipation of a seasonal pick-up in construction activity," according to S&P Global Commodity Insights analyst Ronald Cecil.

Prices have fallen from year-ago levels, when the IODEX 62% iron ore price benchmark hit $162.75/t on March 7, 2022, amid supply concerns stemming from Russia's February invasion of Ukraine and expectations of further government-led support for China's economy.

Australia's Fortescue Metals Group Ltd. was the only miner among the top five iron ore producers to book lower year-over-year output. Meanwhile, BHP Group Ltd. had the smallest year-over-year growth among the top five at 89,000 metric tons or 0.1%.

Rio Tinto's year-over-year tonnage increase was nearly triple that of the next biggest improver, Brazil's Companhia Siderúrgica Nacional, whose first-quarter output increased by 2.5 MMt or 38.8% year on year to 8.9 MMt.

The largest five miners all reported lower production from the December 2022 quarter.

Metinvest BV had a huge turnaround on a quarterly basis, flipping to a 128.8% rise in production after having the sharpest quarterly drop in the previous quarter due to disruptions caused by the Ukraine conflict. Despite the jump, Metinvest's first-quarter output was still lower year on year by 3.8 MMt or 62.4%.

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