Resource Upgrade Boosts Chilwa’s Project, But Key Assays and Feasibility Await

Resource Expansion and Confidence Upgrade

Chilwa Minerals Limited (ASX, CHW) has delivered a substantial boost to its mineral resource base within the Chilwa Critical Minerals Project in southern Malawi. The company’s updated JORC 2012 Mineral Resource Estimate (MRE) reveals an 85% increase in contained Total Heavy Minerals (THM), now standing at 4.44 million tonnes within a total ore volume of 110 million tonnes grading 4.03% THM. Notably, 71% of this resource is classified as Indicated, a significant upgrade from the previous all-Inferred status, enhancing the project's credibility for advancing feasibility studies.

Drilling and Assay Advances Drive Results

This resource expansion is underpinned by a rigorous combination of historic Aircore drilling and more recent Sonic drilling campaigns. The Sonic drilling, favored for its superior preservation of geological boundaries in unconsolidated mineral sands, has provided higher resolution data, particularly at key deposits such as Mposa and Mpyupyu Dune. The integration of these datasets, alongside comprehensive assay work including Heavy Liquid Separation and mineralogical analysis via QEMSCAN, has refined grade estimates and confidence levels.

Enhanced Mineral Grades and Deposit Highlights

Alongside the volume increase, Chilwa has reported improved mineral grades, with ilmenite rising from 3% to 3.23% and rutile averaging 0.11% across deposits. The Mpyupyu Dune deposit stands out with exceptionally high grades, reinforcing the project's potential. Other deposits such as Bimbi, Halala, and the Northern Shore deposits contribute to a diversified resource portfolio. The mineral assemblage also includes zircon and minor rare earth elements, adding further value.

Pathway to Economic Extraction and Scoping Study

Chilwa’s Managing Director, Cadell Buss, emphasized the milestone as validation of the project's viability, highlighting the commencement of mine feasibility studies with TZ Minerals International (TZMI). The scoping study, scheduled for delivery in the second half of 2025, will leverage the upgraded resource data to evaluate mining and processing options. The company anticipates dry mining methods with high recovery metallurgical processes, supported by prior studies from SGS, Mintek, and AML.

Environmental and Operational Considerations

The project area, while adjacent to the Ramsar-designated Lake Chilwa wetland, is situated on elevated grasslands used for agriculture, minimizing direct environmental impact. Chilwa plans to implement responsible mining practices, including backfilling tailings and managing slimes appropriately. The company’s in-country sample preparation facility and stringent QAQC protocols underscore its commitment to operational excellence and data integrity.

Looking Ahead

With further assay results pending from ongoing sonic drilling programs and additional MRE updates anticipated, Chilwa Minerals is poised to refine and potentially expand its resource base further. The company’s strategic focus on advancing the Chilwa Critical Minerals Project positions it as a promising player in the mineral sands sector, with a growing resource footprint and a clear pathway toward economic extraction.