Heavy Rare Earths Uncovers High-Grade Heavy Rare Earth Zones at Subron Project

Subron Project Reveals Exceptional Heavy Rare Earth Mineralisation

Heavy Rare Earths Limited (ASX:HRE) has unveiled preliminary results from a strategic review of its Subron Rare Earths Project in Western Australia, formerly known as Cowalinya. The review highlights a rare and valuable concentration of heavy rare earth oxides (HREO), with the project boasting a peak HREO ratio of 70%, positioning it among the highest-grade residual clay deposits of its kind.

The company identified approximately 12.9 kilometres of mineralised strike hosting high-grade HREO across ten distinct domains. This mineralisation sits within a substantial JORC resource of 159 million tonnes grading 870ppm total rare earth oxides (TREO). Notably, the Seawolf prospect emerged as a priority target, delivering a remarkable intercept of 8 metres at 3057ppm TREO with an average 42% HREO ratio from 27 metres depth.

Drilling Data Supports High-Value Heavy Rare Earth Zones

The review analysed a comprehensive drill database comprising 547 aircore holes, revealing 190 significant intercepts exceeding 1000ppm TREO with an average grade of 1685ppm TREO and 441ppm HREO, equating to a 25% HREO ratio. More impressively, 150 intervals surpassed 300ppm HREO, averaging 1653ppm TREO with 579ppm HREO, pushing the HREO ratio to 38%. These figures underscore the project's potential to yield a concentrate rich in strategic heavy rare earth elements such as europium, gadolinium, terbium, dysprosium, and yttrium.

Heavy Rare Earths’ Managing Director Jason Barnett emphasised the value proposition: "These exceptional high-grade HREO ratio zones may be amenable to concentrate and yield a far higher value proposition for processing. It’s still early days and we have a lot of work to do on mineralogy, re-domaining the resource and metallurgical testwork, but with a significant amount of work done already, we have a head start."

Structural Controls and New Naming Reflect Strategic Vision

The mineralised domains at Subron are structurally controlled, elongated, and parallel to regional geological features. The company has named these structural corridors after submarine-related seas (Barents, Bering, Bismarck), reflecting the interpreted submarine-like geometry of the mineralisation. This inspired the project's new name, Subron, short for Submarine Squadron, symbolically linking the deposit’s strategic heavy rare earths to demand in next-generation submarine technology, notably the AUKUS program.

Consultant Claudio Sheriff, an expert in rare earth discoveries, noted the significance of the findings: "Residual clay occurrences aren’t rare, however a cluster of HREO domains in a sea of regional prospectivity, emerging at Subron, are remarkable. The preliminary findings are awakening a re-rate at Subron as understanding of its composition evolves."

Strategic Location and Next Steps for Resource Development

Strategically, Subron is well positioned 110km NNE of Esperance port and 350km south of the Kalgoorlie Rare Earth Processing Facility, enhancing logistics for future development. The project tenure is on unallocated crown land with full native title rights granted to the Ngadju people, ensuring cultural heritage considerations are met.

Looking ahead, Heavy Rare Earths plans to re-domain the current JORC resource to better define high-grade zones, initiate metallurgical testwork focusing on specific geological layers to simplify processing, and conduct infill drilling aimed at upgrading resource classifications from Inferred to Indicated. The company is also exploring the use of existing aircore drilling samples to fast-track metallurgical studies without the need for immediate re-drilling.

This strategic review lays a foundation for unlocking the value of Subron's high-grade heavy rare earth deposits, but significant work remains to translate these promising geological findings into a commercially viable resource.