Stellar’s strong Heemskirk tin recoveries pave way for premium product
Stellar’s testwork on the Severn deposit confirms the potential to produce a premium tin concentrate from Heemskirk project in western Tasmania.
Stellar Resources completes metallurgical testwork on core samples from Severn deposit
The program highlighted total tin recoveries of 75% and tin concentrates grading 45-50%
PFS underway, set for release in 2026
Special report: Encouraging test results on ore from Severn deposit at the Heemskirk tin project in western Tasmania reinforce the potential for Stellar Resources to deliver a clean, high-value tin concentrate.
Metallurgical testwork by ALS Metallurgy in Burnie on six composite samples showed strong tin recoveries and low impurity concentrate grades, confirming earlier studies and giving the company greater confidence in its processing flowsheet.
Sequential gravity and sulphide removal testing achieved potential recoveries of 75% tin, producing concentrates grading 45-50% tin, closely aligned with the 76.4% recovery reported by Renison in the September quarter from its nearby operations.
Stellar Resources' (ASX:SRZ) work, overseen by Geoff Beros, former chief metallurgist at the Renison Bell operation, shows that the orebody’s mineralogy appears favourable, with very low levels of common smelter penalty elements, suggesting Heemskirk could produce an attractive, high-payability concentrate.
The company said the results validated a conventional gravity and flotation flowsheet, and highlighted avenues for further gains through sulphide float optimisation, fine-tin recovery and regrind control.
With a stronger metallurgical foundation in place, the company has started early discussions with potential offtake partners, supported by growing interest seen at the recent Asia Tin conference in Hong Kong.
Background on Heemskirk
Heemskirk is near the mining town of Zeehan on Tasmania’s west coast and consists of three tin deposits including Severn - the largest orebody in the project area - Queen Hill and Montanta.
Heemskirk has indicated and inferred resources of 7.5Mt grading 1.04% tin with infill drilling along of the inferred sections at Severn and Queen Hill set to deliver an conversion to indicated resources for the PFS.
A recent wedge hole at Severn, which intersected 25m at 0.38% tin from 539m, including a high-grade core of 4m at 1.26% from 546m, represents the first of multiple wedge holes planned to execute the resource conversion strategy.
Listen: Stellar eyes its entry into an ascendant market
PFS wrapping up before 2026 release
SRZ Managing Director and CEO Simon Taylor said the program has confirmed the quality metallurgical properties of the Severn deposit.
“The dominance of pyrite with only trace levels of arsenopyrite, chalcopyrite, sphalerite and galena mean our concentrate will carry very low smelter penalties, a major commercial advantage,” he said.
“This low-penalty mineralogy provides a significant commercial and strategic advantage over impurity-rich feed sources from Africa, South America and Southeast Asia, where arsenic, bismuth and lead often exceed smelter acceptance limits and reduce payability.
“The Heemskirk concentrate is anticipated to attract strong demand from established smelters seeking sustainable, traceable, and low-impurity feedstocks, particularly in a tightening global tin market.”
The PFS metallurgical testwork is now in its final stage, running in parallel with the updated resource estimate, mine planning and engineering work.
All of these technical aspects will be brough together in the PFS, which Stellar is targeting for completion in H1 2026.
This article was developed in collaboration with Stellar Resources, a Stockhead advertiser at the time of publishing.
This article does not constitute financial product advice. You should consider obtaining independent advice before making any financial decisions.
