Highlights

  • Laboratory assays from a scissor pair of diamond holes have confirmed continuous niobium mineralisation across the Nakombe discovery in Malawi.
  • The results replace earlier portable XRF readings, which understated niobium grades, and highlight yttrium-rich rare earths alongside tantalum and gallium.
  • Infill drilling continues with multiple rigs ahead of a planned maiden Mineral Resource Estimate, while the existing exploration target remains conceptual.

Critical minerals continue to draw attention across the Australian market as governments and manufacturers look for new sources of metals used in steelmaking, electronics and advanced technologies. Niobium, a metal valued for strengthening steel and for emerging battery applications, is part of that conversation. Chilwa Minerals Ltd (ASX:CHW), an explorer with heavy mineral sands and critical minerals interests in Malawi, has released laboratory assays from its Nakombe niobium and rare earth discovery. The results point to a sizeable mineralised system and position the company among Metal and Mining Stocks pursuing early-stage critical minerals discoveries in Africa. The update also confirms that drilling remains active as the company works toward a maiden resource estimate.

Laboratory Assays Confirm Continuous Mineralisation

The latest results come from a scissor pair of diamond holes drilled from opposite ends of the Nakombe target on opposing directions. Chilwa reported that laboratory assays confirm continuous niobium mineralisation between the holes along the tested strike, with the northern hole returning a broad niobium interval starting at surface, including a higher-grade zone at shallow depth.

The southern hole intersected niobium mineralisation at depth and remained mineralised to the end of the hole. Chilwa noted that the upper part of the northern hole also carried tantalum and gallium, both of which are recognised as critical minerals in several jurisdictions.

Scissor drilling, where holes are angled toward each other from opposite sides of a target, is a common technique for testing the geometry and continuity of mineralisation. In this case, the pairing allowed Chilwa to test the system from both ends, and the company has said the outcome supports its view that Nakombe hosts a large intrusion-related niobium and rare earth system.

Assays Replace Earlier Portable XRF Readings

Chilwa had previously reported indicative portable XRF readings for these holes. The new laboratory results, generated by inductively coupled plasma mass spectrometry, supersede those figures and show that the portable readings had understated niobium grades in both holes.

Laboratory assays are generally considered more reliable than handheld instruments for reporting grade, so the update provides a firmer data set for geological modelling. Market Participants should rely on the laboratory results rather than the earlier indicative readings when considering the project.

Yttrium-Rich Rare Earths Add Another Dimension

Beyond niobium, the assays show rare earth mineralisation with a notable yttrium component. The deepest portion of the southern hole returned niobium alongside rare earth oxides in which yttrium oxide made up a meaningful share, while the northern hole also carried rare earths across its full length.

Managing Director Cadell Buss highlighted the rare earth credentials of the system, pointing to yttrium, tantalum and gallium. He described the laboratory results as a key input toward the company's maiden Mineral Resource Estimate. Yttrium has drawn growing attention as Supply chains for certain heavy rare earths remain concentrated.

Important Exploration Caveats

All reported intervals are downhole widths, and true widths are not yet known. Chilwa has an exploration target for Nakombe South, but this is conceptual in nature. There has been insufficient exploration to estimate a Mineral Resource, and it is uncertain whether further work will lead to a resource being defined.

The company has said mineralisation remains open in several directions. Metallurgical understanding is still at an early stage, with particle mineral analysis on composite samples underway to determine how niobium and rare earths are hosted. These results will help guide the next drilling phase and inform resource work.

Drilling Programme and Path to a Maiden Resource

Chilwa has several diamond rigs active at Nakombe, with remaining infill holes on the southern part of the target scheduled for completion before the end of this year. Drilling at the Nakombe North target is planned to resume next year.

The company has provisionally planned its maiden Mineral Resource Estimate for the middle of next year, drawing on completed and planned drill holes. Timelines for exploration programmes can shift with drilling conditions, laboratory turnaround and technical findings, so these milestones remain targets rather than certainties.

Chilwa also continues to hold heavy mineral sands interests in Malawi, giving it exposure to more than a single Commodity theme. However, for many market participants the Nakombe discovery has become a central focus, and the coming months of infill drilling and mineralogical work are likely to shape how the project is defined.

Building the Case at Nakombe

Chilwa Minerals' laboratory assays strengthen the geological picture at Nakombe, confirming continuous niobium mineralisation and highlighting yttrium-rich rare earths, tantalum and gallium. The project nonetheless remains at an exploration stage, with true widths unknown, a conceptual exploration target and metallurgy still under study. For Australian readers, the update adds to the broader theme of ASX-listed explorers seeking diversified critical minerals supply, a segment shaped by drilling results, resource definition and evolving global demand.