The Simandou iron ore project in Guinea, developed with Chinese state partners, reached an annualized production rate of about 10 million tons in the third quarter, Rio Tinto said in its quarterly operations review. The SimFer mine, which Rio Tinto runs with a consortium led by China's Chinalco, produced 2.5 million wet tons in the three months to September, up 273% from the second quarter.

For Asian steelmakers and iron ore traders, Simandou matters because almost every ton goes to China. At full capacity the project is designed to export up to 120 million tons a year, and it gives Chinese state companies a source of ore outside Australia and Brazil. Its ramp-up pace is one of the inputs traders watch when they price the benchmark 61% iron ore contract, which averaged about $97 a dry ton delivered to China in the quarter, according to Rio Tinto.

Rio Tinto's Simandou figures show ore piling up

Production is running ahead of the export chain. SimFer shipped 2.2 million tons to China in the third quarter, the Rio Tinto report showed, but recognized sales were only 1.3 million tons, because ore takes months to reach Chinese buyers. In the first nine months of the year the mine produced 3.7 million tons on a 100% basis and shipped 4.4 million tons, including ore recorded in late 2025.

By the end of September, 7.9 million tons of uncrushed ore sat at the mine. Counting material at the Guinean port, on ships and at Chinese ports, the total across the system was 11.1 million tons. Rio Tinto said that at full output it is aiming for a 75-to-90-day cycle from mine to recognized sale, with customers taking up to another 30 days to collect.

Part of the reason is that the permanent plant is not finished. Simandou ore currently leaves Guinea only partly processed: final crushing is done in China. Rio Tinto said the mine was about 84% complete and that it expects first ore through one of its two primary crushers in the fourth quarter. The SimFer port and marine works were 92% complete, and the first transshipment vessel arrived in Guinea late in the quarter. Until that port opens, SimFer ore moves through the barge port built by its partner, Baowu Winning Consortium Simandou.

Rio Tinto kept its 2026 guidance for Simandou sales at 5 million to 10 million tons and said the mine remains on track to reach a run rate of 60 million tons a year in the second half of 2028. Chief Executive Simon Trott said the company's major projects were on schedule and budget. Rio Tinto's share of the project's capital cost is $6.2 billion.

Chinalco and Baowu hold the Chinese stakes

Simandou is split into four blocks. SimFer, which owns 85% of the mine in blocks 3 and 4 with the Guinean government holding 15%, is a partnership between Rio Tinto and CIOH, the Chinalco-led consortium. Blocks 1 and 2 belong to the Winning consortium, in which Baowu, the world's largest steelmaker, took control early this year.

Baowu Resources raised its stake in the Winning Consortium Simandou to 51% from 49%, Reuters reported in February, and the Singapore-registered company and its Guinean arm were renamed Baowu Winning Consortium Simandou. The deal was completed on Jan. 30. That group built the roughly 536-kilometer dual-track main rail line to the coast, Rio Tinto's report said, while SimFer built its own spur of about 70 kilometers and a transshipment port.

The first cargo left Guinea on Dec. 2, 2025, aboard the bulk carrier Winning Youth, bound for Majishan in China, Argus Media reported in March. At that time the main limit on exports was rail capacity. Ifchor Galbraiths, a shipbroker, told Argus that 2026 output was limited by rail logistics, noting that only eight locomotives had been deployed.

Ramp-up pace is the number to watch

Exports have since picked up. Shipments from the Morebaya port reached 2.2 million tons in May, a record, according to Kpler ship-tracking data cited by Bloomberg in June. Ifchor Galbraiths forecast at the time that third-quarter exports from the whole project could reach as much as 8 million tons, and fourth-quarter exports 12 million tons.

SimFer's own pace has been steadier. It shipped 1.6 million tons to China in the second quarter and 2.2 million tons in the first half, the joint venture said in August, after the rail network was fully commissioned in the first quarter. It said it had spent $210.5 million with Guinean suppliers so far this year. Rio Tinto said the SimFer workforce across mine, rail and port totals 17,430, of whom 75% are Guinean.

The extra supply arrives as Chinese demand softens. Rio Tinto estimated that China's finished steel consumption fell about 4% from the second quarter and 2% from a year earlier, while steel exports rose 3% from a year earlier to an annualized 122 million tons. China's domestic iron ore output dropped 8% in the quarter from a year earlier, which helped absorb new imports.

The next checks come in the fourth quarter, when Rio Tinto expects first ore through one of the two SimFer primary crushers and through the SimFer port. After that, full-year Simandou sales will be measured against Rio Tinto's 5 million-to-10 million-ton guidance.