Heavy Rare Earths Expands Subron Project by 268% Securing High-Grade HREO Extensions

Subron Project Footprint Triples with Strategic Tenure Acquisition

Heavy Rare Earths Limited (ASX:HRE) has significantly expanded its Subron Rare Earths Project in Western Australia, increasing the landholding by 268% to 562 square kilometres. The company secured two new tenement applications covering 142 blocks (410 km²) contiguous with its existing Subron tenure. This low-cost acquisition, with application fees and rent under $30,000, strategically captures interpreted strike extensions of high-grade heavy rare earth oxide (HREO) domains at the Blume, Hunley and Seawolf prospects.

These prospects have already delivered exceptional drill results, including intercepts such as 3 metres at 2,246 ppm total rare earth oxides (TREO) with a 66% HREO ratio, and 8 metres at 3,057 ppm TREO with 42% HREO. The expanded tenure now hosts more than 50 kilometres of sub-parallel structural corridors considered highly prospective for HREO mineralisation trends, substantially increasing the project's exploration runway.

Strategic Review Uncovers Multiple High-Value Targets

The tenure expansion follows a strategic review led by rare earth consultant Claudio Sheriff, who identified multiple structural corridors within regional magnetic data that align with high-grade HREO mineralisation. The review interprets at least 10 distinct high-grade HREO domains named after submarines, reflecting the project's previous codename and the substantial rare earths required in submarine construction.

Applying a >300 ppm HREO cut-off to existing drill data reveals 150 significant intercepts and 454 individual 1-metre intervals grading above this threshold, averaging 1,653 ppm TREO with a 38% HREO ratio. The newly acquired tenements secure the interpreted strike extensions of the standout Blume, Hunley, and Seawolf prospects, which remain priority targets for further drilling to upgrade resource confidence from Inferred to Indicated.

High-Grade Heavy Rare Earths with Strategic Element Composition

Subron’s mineralisation is notable for its high proportion of valuable heavy rare earth oxides such as yttrium, terbium, and dysprosium, elements critical for next-generation technologies and defence applications. The distribution of these elements within the >300 ppm HREO dataset underscores Subron’s potential as a significant supplier of these strategic minerals.

Preliminary metallurgical testwork has shown promising recoveries, with up to 91% TREO recovery using mild hydrochloric acid leaching. The company plans to fast-track heritage access on the new tenements to enable drilling of the newly identified mineralised corridors, aiming to bolster the global resource base and refine the mineralogical characterisation.

Advancing Towards Resource Definition and Value Unlocking

Heavy Rare Earths is actively progressing workstreams to enhance Subron's resource quality and economic potential. This includes discussions with resource geologists to re-domain the current JORC mineral resource, focusing on producing a smaller tonnage but higher value high-grade HREO resource. Additional metallurgical testwork targeting specific geological layers aims to simplify processing flowsheets, while infill drilling is planned to convert Inferred resources to Indicated and extend high-grade domains.

Located close to Esperance port and the Kalgoorlie Rare Earth Processing Facility, Subron’s expanded footprint and high-grade mineralisation position it as a compelling project in the critical minerals sector. The company anticipates further updates on the strategic review and exploration results in the coming weeks, which will be crucial for assessing Subron’s path towards development.