Chilwa’s Carbonatite Discovery Raises Stakes in Critical Rare Earth Race

• Completion of soil sampling on 30 of 47 geophysical REE targets
• Identification of multi-element anomalies including heavy rare earth elements and niobium
• Diamond drilling in progress at Mposa anomaly confirming carbonate veining
• Heavy REE anomalies prioritized for further drilling
• Dual focus on rare earth elements and mineral sands within the project

Confirming a Carbonatite Swarm

Chilwa Minerals Limited (ASX: CHW) has delivered a compelling update on its Lake Chilwa Critical Minerals Project in southern Malawi, confirming the presence of a significant swarm of carbonatite intrusions enriched with rare earth elements (REEs). Following extensive surface soil sampling and rock-chip geochemistry across 30 of 47 geophysical targets identified in 2024, the company has delineated robust multi-element anomalies that include both light and heavy REEs, alongside key pathfinder elements such as niobium, barium, and zirconium.

The recent sampling campaign analyzed 121 soil samples and 24 rock-chip specimens, revealing ionic soil geochemistry anomalies that range from 10 to over 500 times background levels for total rare earth oxides (TREO). These results reinforce earlier findings announced in January 2025 and align closely with detailed aeromagnetic and radiometric surveys, underscoring the geological coherence of the carbonatite mineral system beneath the project area.

Heavy Rare Earths Take Centre Stage

Of particular note is the enrichment of heavy rare earth elements (HREEs) such as yttrium, dysprosium, and erbium within several target zones, including the Mposa anomaly where diamond drilling is actively underway. HREEs are considered critical metals due to their strategic importance in high-tech and clean energy applications, making Chilwa’s findings especially significant in the context of global supply constraints.

Drill core retrieved from the Mposa site has already demonstrated near-surface carbonate veining and stockwork within nepheline syenite, providing tangible geological evidence supporting the carbonatite model. Assay results from the ongoing diamond drilling program are expected within the next four to six weeks and will be pivotal in assessing the economic potential of the mineralisation.

Strategic Dual-Track Exploration

Chilwa Minerals continues to pursue a twin strategy, simultaneously advancing exploration for both rare earth elements and mineral sands within the licence area. The mineral sands component has shown promising thickened sequences with high-grade assemblages, while the REE program is focused on prioritizing alkaline intrusion targets associated with carbonatites.

The company’s methodical approach includes detailed geochemical fingerprinting to understand element zoning and mineralogical controls on REE distribution, leveraging both local and international analogues. This scientific rigor enhances confidence in target prioritization and resource delineation.

Looking Ahead

With 17 priority REE targets still to be sampled and a diamond drilling campaign progressing, Chilwa Minerals is well positioned to expand its understanding of the rare earth mineral system at Lake Chilwa. The establishment of an on-site sample preparation laboratory at Zalewa is expected to improve assay turnaround times, accelerating the pace of exploration.

As the company awaits assay results from the Mposa drill holes, investors and industry watchers will be keen to see whether the promising geochemical signatures translate into economically viable mineral resources. The Lake Chilwa project’s location within a region known for carbonatite-hosted REE deposits adds further strategic value to Chilwa’s exploration efforts.

Bottom Line?

Chilwa’s confirmation of a carbonatite-hosted rare earth system with critical heavy REEs sets the stage for a potentially transformative resource development.

Questions in the middle?

• Will the upcoming drill assay results confirm economically viable heavy rare earth mineralisation?
• How will Chilwa prioritize and sequence drilling across the remaining untested REE targets?
• What are the potential timelines and capital requirements to advance the project towards resource definition?