Between rare earth oxide and the magnet there is a step that almost only China masters. A Chilean steelmaker decided to learn it

Aclara and CAP opened a demonstration plant in Chile that turns neodymium and praseodymium oxides into metal. The case shows why metallisation is the forgotten link in the chain — and how skills from another industry can unlock it.

Aclara Resources and CAP, Chile's largest steel group, opened a demonstration plant to produce rare earth metals and alloys inside the Huachipato steelworks in Talcahuano. The operation belongs to Aclara Metals, a joint venture split equally between the two companies, and was announced in October 2026. The technology is molten salt electrolysis: neodymium and praseodymium oxides are dissolved in a high-temperature salt bath and reduced to metal by electric current. The plant was designed for up to 175 kilograms of metal per day, with minimum purity of 99.5%, and will run production campaigns to test stability. In a second phase, the joint venture is studying the addition of dysprosium oxide to make a neodymium-praseodymium-dysprosium alloy. Because there is no established industrial standard for rare earth metallisation, the electrolytic cell was developed in-house by Aclara Metals and the Huachipato team and is treated as proprietary technology. Data from the demonstration will feed the engineering of an industrial plant planned in Louisiana, in the United States, and digital process optimisation models. The unit complements Aclara's concentration pilots in Chile and Brazil and its separation plant in Virginia.

When people talk about the world's dependence on China for rare earths, the conversation usually stops at mining or at separating the elements. The chain has more links. After separation, neodymium comes out as an oxide, a powder. The permanent magnet that goes into an electric car motor or a wind turbine needs metal. Getting from one to the other — metallisation — is a step of its own, with specific equipment, chemistry and know-how. The dominant route is fluoride-based molten salt electrolysis at around 1,050 °C. It requires fine control of oxygen and impurities, refractories that can withstand the corrosive bath and experienced operators. China accounts for about 90% of rare earth separation and metal processing, and the announced metals and alloys capacity outside the country is estimated by the International Energy Agency at just 18,000 tonnes. For comparison: a single Chinese company, Northern Rare Earth, budgeted about 45,000 tonnes of neodymium and NdPr metal for 2025. That is why a country can have a mine and a separation plant and still remain dependent — the oxide travels to the other side of the world to become metal. The Chilean partnership teaches a second, subtler lesson: where the missing competence comes from. A steelworks does not produce rare earths, but it has lived for decades with liquid metal, furnaces, electrodes, refractories and metallurgical quality control. Aclara brings the ore and the separation chemistry; CAP brings the culture of operating high-temperature processes safely. It is a transfer of competence between sectors, not the purchase of ready-made technology — not least because, outside China, it is not for sale. The format of the plant is also instructive. At 175 kilograms per day, the demonstration does not exist to generate revenue. It serves to train teams, find out how the cell behaves over long campaigns and generate real data to size the industrial unit. Skipping that step in a process with no established standard would mean betting the investment on an extrapolation.

Diversifying the magnet chain requires covering every step, and metallisation is one of the narrowest. For Brazil, where ionic clay rare earth projects are advancing — including Aclara's own concentration pilots —, the lesson is direct: extracting and separating is not enough to capture value if the metal is still made elsewhere. For metallurgical engineers, molten salt electrolysis and cell design are scarce skills, in growing demand in critical minerals programmes across the Americas, Europe and Australia.