Resource Upgrade Potential at Heemskirk as High-Grade Tin Zone Remains Open

Significant Drill Results at Queen Hill

Stellar Resources Limited (ASX: SRZ) has announced a standout drilling result from its Queen Hill deposit within the Heemskirk Tin Project in Western Tasmania. Drillhole ZQ173 intersected a broad, high-grade tin zone measuring 23.3 metres at 2.20% tin (Sn), including narrower intervals grading above 3.4% Sn. This intersection lies approximately 95 metres below a previously reported hole (ZQ170) and notably exceeds the width and grade of the existing resource model in this area.

The new data is particularly encouraging as it targets a zone previously classified as Inferred mineralisation, with the potential to upgrade it to the Indicated category. Such an upgrade is critical for advancing the project’s development and will feed directly into the ongoing Prefeasibility Study (PFS), scheduled for completion in the second half of 2025.

Exploration and Resource Expansion Strategy

The drilling campaign at Heemskirk is part of a 24-hole program totaling approximately 9,500 metres, with 12 holes and nearly 6,000 metres completed to date. Three rigs are currently operational, focusing on infill and extension drilling to bolster resource confidence and size. Alongside the high-grade intercepts, multiple lower-grade tin zones were also intersected further downhole, underscoring the fertile nature of the Heemskirk system.

Complementing the drilling, Down Hole Electromagnetic (DHEM) surveys conducted on hole ZQ173 have identified a conductive body extending along strike and to the south, presenting a compelling target for deeper follow-up drilling. This geophysical insight could unlock further extensions to the mineralised zone, which remains open at depth and plunge.

Implications for Production and Project Economics

Stellar’s Managing Director, Simon Taylor, highlighted the significance of these results, noting the potential to increase metal production beyond the previous scoping study’s base case of 1,900 tonnes per annum over 12 years. The company now aims for a production rate of 3,000 to 3,500 tonnes per annum over the first 6 to 10 years, reflecting confidence in the resource growth and metallurgical advancements, including promising ore sorting results recently announced.

These developments position Heemskirk as Australia’s highest-grade undeveloped tin resource and among the top globally, with a current resource estimate of 7.48 million tonnes at 1.04% Sn containing nearly 78,000 tonnes of tin. The ongoing PFS will integrate these new drilling results and metallurgical data to refine project economics and mine planning.

Challenges and Next Steps

While drilling at the Severn deposit, another key area within Heemskirk, has faced difficulties due to challenging ground conditions, Stellar is trialling alternative drilling methods to improve effectiveness. The current focus remains on Queen Hill to secure metallurgical samples for early production years. Once this phase is complete, resources will shift back to Severn with improved drilling techniques.

Looking ahead, further DHEM surveys and deeper drilling are planned to test the down-dip and plunge extensions of the mineralisation. The company’s methodical approach to resource conversion and expansion, combined with robust metallurgical testing, aims to deliver a development-ready project with strong production potential.