IMC Rare Earths reports high terbium recovery in Brazil tests

IMC Rare Earths reported laboratory-scale metallurgical results from its Itarantim ionic adsorption clay project in Brazil, highlighting a maximum terbium recovery of 95.2%. The tests, conducted with the Instituto Federal do Rio Grande do Norte, focused on extracting four magnet rare earth elements: neodymium, praseodymium, dysprosium, and terbium. The company stated that the best-performing composite, designated COMP C2, averaged 81.1% terbium recovery while reaching the 95.2% peak in specific trials.

These findings occur against a backdrop of significant geopolitical concentration in the rare earth supply chain. The International Energy Agency noted that China accounted for 60% of mined magnet rare earth production, 91% of refined output, and 94% of sintered permanent magnet production in 2024. Recent export controls by China’s Ministry of Commerce, specifically targeting terbium products and NdFeB magnet materials, have intensified the search for alternative processing routes outside of Chinese infrastructure.

Metallurgical test results and composite performance

The testwork evaluated the separation efficiency of individual elements from the clay ore. Across the tested material, average recoveries were recorded as 66.1% for neodymium, 36.5% for praseodymium, 46.1% for dysprosium, and 81.1% for terbium. The ranges for these elements were 51.8% to 77.7% for neodymium, 33.1% to 41.1% for praseodymium, and 31.3% to 55.6% for dysprosium. Terbium showed the widest range, extending from 56.6% to 95.2%. The process also produced a mixed rare earth carbonate via a hydrometallurgical route, an intermediate material intended for further processing to isolate specific elements.

The metallurgical results were reviewed and approved by Alexandre Rocha da Rocha, a tenured geology professor at the Federal Institute of Rio Grande do Norte. He served as the qualified person under Subpart 1300 of Regulation S-K for the company's disclosure. The collaboration with the EMBRAPII-affiliated CT Mineral laboratory provided the technical framework for these initial extraction metrics, though they remain preliminary laboratory data rather than field-proven industrial outputs.

Itarantim resource definition and geological uncertainty

IMC describes Itarantim as an early-stage resource located in the Brazilian states of Bahia and Minas Gerais. Drilling has identified an Inferred Mineral Resource of approximately 1.1 billion tonnes with an average grade of 1,233 parts per million total rare earth oxides. A specific inferred domain of 105.8 million tonnes shows an average reported terbium concentration of 8 parts per million. Under the SEC’s mining disclosure framework, the Inferred classification indicates a higher level of geological uncertainty and does not establish economic viability or commercial feasibility.

Development constraints and revenue outlook

The company explicitly states that these laboratory findings do not establish a commercial recovery rate, production volume, processing cost, or profitability. IMC identifies itself as an exploration and development company with no operating revenues and does not anticipate generating revenue in the foreseeable future. Additional exploration and technical studies are required to determine if the deposit can support a viable development. The current results represent a single data point in a longer development process, confirming the technical potential of the ore body without demonstrating that it can be mined or processed economically at scale.