IMC Rare Earths Reports Yttrium Grades up to 3,099 Ppm in Brazil

IMC Rare Earths Ltd (IMC ) on October 29, 2026 announced what it described as two high-grade yttrium-rich discoveries at its Itarantim ionic adsorption clay rare earth project in Brazil, reporting a shallow intersection of 7 meters grading 2,052 parts per million (ppm) yttrium oxide from 2 meters below surface at Block H and a separate 13-meter intersection at Block D that remained mineralized when drilling stopped. The results were released as Exhibit 99.1 to a Form 6-K filed with the U.S. Securities and Exchange Commission.

The company characterized the findings as exploration-stage results and stated that further drilling and metallurgical work are required to establish their extent and commercial potential.

Block H and Block D Results

At Block H, hole AD-00555 intersected 7 meters grading 2,052 ppm yttrium oxide from 2 meters below surface, including 3 meters at 2,836 ppm, with a peak one-meter sample of 3,099 ppm, according to the release. Yttrium oxide accounted for 36% of total rare earth oxides across the interval, compared with a median of approximately 10% in the Itarantim drilling database. IMC states that the peak grades rank among the top five of more than 870 drill holes in the project database.

At Block D, hole AD-00403 returned 13 meters at 1,287 ppm yttrium oxide from 14 meters depth, including 3 meters at 2,464 ppm, and ended in mineralization at 27 meters. Within that interval, 9 meters averaged 982 ppm yttrium oxide with an estimated 84% yttrium extraction. The broader 13-meter interval also contained 1,457 ppm magnet rare earth oxides, and yttrium formed 26% of the rare earth content at Block D.

“Yttrium accounts for more than a third of the rare earth oxides in the Block H interval,” said Frank Scolaro, Chief Executive Officer and Chair of IMC Rare Earths. “This discovery could shape the product we ultimately seek to produce, adding yttrium to the group of rare-earth metals at Itarantim, alongside dysprosium and terbium.” Scolaro said yttrium is used in semiconductor equipment, aerospace components, lasers and advanced ceramics, and that the company’s job now is to establish how far the zones extend and to confirm their extraction performance through further testwork.

Measurement Method and Planned Work

In six Block H samples and ten Block D samples, yttrium in the leach solution exceeded the 500 ppm upper measurement limit of the ALS laboratory test, according to an appendix to the release. For those over-limit samples, IMC estimates yttrium leach extraction as 1.057 times the average dysprosium, holmium and erbium leach plus 2.5, a relationship it states was fitted on 1,955 database samples with in-range yttrium and that carries a standard error of plus or minus 4.6 percentage points. The release states that the estimates are not assay results.

All holes are vertical and sampled at one-meter intervals from surface, with samples submitted to ALS in Vespasiano, Minas Gerais, for ME-MS81d and ME-MS19 ammonium sulfate leach analysis, according to the company. Sample batches include blanks, field duplicates and certified reference materials under the company’s QA/QC protocol.

The scientific and technical information in the release, including the estimated yttrium leach extractions, was reviewed and approved by Alexandre Magno da Rocha, a Qualified Person as defined in Subpart 1300 of Regulation S-K. The release describes da Rocha as a geologist with more than 40 years of mineral exploration experience in Brazil and internationally and as a tenured professor of geology at the Federal Institute of Education, Science and Technology of Rio Grande do Norte. Da Rocha is a director of IMC Rare Earths and is not independent of the company.

For Block H, IMC plans infill and step-out drilling to define the extent, thickness and continuity of the shallow, high-grade yttrium zone, with ammonium sulfate leach testing on all mineralized samples. At Block D, the company plans diamond drilling to test the full yttrium-enriched zone beneath the hill, below the reach of existing auger drilling, together with step-out drilling around AD-00403 to expand the yttrium-rich and magnet rare earth domains. Representative material will be collected for metallurgical testwork at ANSTO in Australia, work the company states will provide a direct measure of yttrium extraction from the high-grade zones.

IMC states that the potential quantity and grade of the Block H and Block D yttrium zones are conceptual in nature, that exploration to date has been insufficient to estimate a mineral resource in these areas, and that it is uncertain whether further exploration will result in the estimation of a mineral resource. The company also states that the estimated yttrium leach extractions are subject to confirmation and that no economic study has been completed on Block H or Block D.

The Form 6-K, a report of foreign private issuer for October 2026, was signed on October 29, 2026 by Chairman and Chief Executive Officer Francesco Scolaro and lists the company’s principal executive office at Avenida Paulista 1765, 7th Floor, São Paulo, Brazil. The EDGAR submission header records the submission’s acceptance at 08:16:30 on October 29, 2026.

On its corporate website, IMC describes Itarantim as a dysprosium and terbium project and states that it holds a 1.1 billion-tonne inferred resource defined from only part of the land package, with a 1.5 billion-tonne exploration target it aims to test. The company’s investor relations newsroom lists earlier 2026 announcements dated July 28 for the pricing of its initial public offering, July 29 for the start of trading on NYSE American under the ticker IMC, September 10 for terbium recoveries of up to 95.2% at Itarantim, and September 22 for a 73% in-situ rare earth recovery.