Core Energy Confirms Consistent Rare Earth Grades and Significant Yttrium Enrichment at Tunas Project

• Second-phase infill auger drilling confirms lateral continuity
• High TREO and MREO grades with up to 637 ppm Y2O3
• Mineralisation remains open and strengthens at depth
• Geochemical profile supports ionic adsorption clay model
• Leachability testwork underway to assess extraction potential

Consistent Rare Earth Mineralisation Confirmed at Tunas

Core Energy Minerals (ASX:CR3) has delivered further validation of its Tunas Rare Earth Element (REE) Project in Paraná, Brazil, revealing thick, near-surface mineralisation with strong total rare earth oxides (TREO) and magnetic rare earth oxides (MREO) grades. The latest assays from the company’s second-phase mechanised infill auger drilling program include standout intercepts such as 14 metres at 2,146 ppm TREO and 555.5 ppm MREO from surface, including 9 metres at 2,672 ppm TREO and 770 ppm MREO starting from 5 metres depth. These results reinforce the lateral continuity of the mineralised horizon and the potential for expansion, as mineralisation remains open at depth.

Yttrium Enrichment Adds Strategic Value

Notably, Core Energy has identified significant enrichment of yttrium oxide (Y2O3) up to 637 ppm, marking the first time this critical heavy rare earth element has been reported at Tunas. Yttrium’s strategic importance is underscored by its applications in advanced ceramics, phosphors, solid oxide fuel cells, and defence technologies, alongside growing geopolitical supply concerns due to Chinese trade restrictions. The presence of elevated yttrium alongside robust TREO and MREO grades enhances the project’s strategic appeal as a potential critical minerals source.

Geochemical Profile Supports Ionic Adsorption Clay Model

The vertical geochemical zonation observed in drill hole TNTR023 highlights increasing concentrations of TREO, MREO, and Y2O3 towards the lower saprolite profile, inversely correlated with a cerium anomaly index. This pattern is characteristic of ionic adsorption clay (IAC) rare earth systems, which are prized for their amenability to low-cost ion-exchange extraction methods. Core Energy is currently conducting leachability testwork to evaluate the ion-exchange potential of the mineralisation, aiming to confirm the applicability of conventional reagents like ammonium sulfate for efficient rare earth recovery.

Project Location and Exploration Outlook

The Tunas Project spans 18.32 square kilometres near Tunas do Paraná, approximately 75 km from Curitiba and 162 km from Paranaguá Port. The mineralisation is hosted within a clay-rich saprolitic horizon developed over weathered biotite gneiss, with no fresh basement intersected to date, leaving the full thickness and extent of the weathered profile open for exploration. Pending positive leach test results, Core Energy plans to advance with geophysical surveys and reverse circulation drilling to further delineate and expand the resource.

Implications for Critical Minerals Supply

These results add to a growing body of evidence positioning Tunas as a promising rare earth project with a meaningful magnet rare earth oxide component and significant heavy rare earth enrichment. The open-ended nature of the mineralisation and ongoing metallurgical studies will be critical in defining the project’s economic viability and its potential contribution to the global critical minerals supply chain amid increasing demand for clean energy and advanced technology materials.

Bottom Line?

Core Energy’s latest assays at Tunas reinforce its rare earth credentials, but pending leachability outcomes will be pivotal in unlocking the project’s full potential.

Questions in the middle?

• Will forthcoming leachability test results confirm efficient ion-exchange extraction?
• How thick and extensive is the mineralised weathering profile beyond current drill depths?
• What are the implications of the significant yttrium enrichment for project economics and market positioning?