Mt Slopeaway Ni-Co Project Update

Australian battery minerals explorer, Firetail Resources Limited (“Firetail” or the “Company”) (ASX: FTL) is pleased to announce the succesful completion of preliminary testwork for its Mt Slopeaway Nickel-Cobalt-Manganese Project in Queensland.

Since the Company successfully completed a five-hole reverse circulation (“RC”) drill program which confirmed and exceeded historical results¹, significant progress has been made in advancing the project and unlocking value for FTL shareholders.

Highlights:

• Completion of a preliminary metallurgical test work program, with all four samples demonstrating excellent amenability for nickel and cobalt recovery using commercial leaching techniques.
• Key notes from testwork are:
  • High nickel extractions (up to 97%) achieved using traditional nickel laterite extraction flowsheet.
  • Cobalt extractions also high but more variable ranging from 58% to 96%.
  • Serpentinite and ferricrete lithology is readily amenable to atmospheric leaching techniques, offering a lower cost alternative production route.
• Land access agreement renewed until April 2024.
• Exploration Permit Minerals (“EPM”) rent waiver granted for Firetail's EPM 26818 and EPM 26848 for five years to 2028 by the Queensland Government under its Critical Minerals Exploration Strategy².
• Preparations for a Phase II drill program consisting of >60 RC & diamond drilling (“DD”) holes well underway, with ground-truthing of collar locations and access tracks completed.
• Application for an Environmental Authority to undertake all required ground clearance in preparation of the Phase II drill program, as well as the completion of Cultural Heritage and Biodiversity Surveys are well advanced.

Executive Chairman, Brett Grosvenor, commented:

“The results of the testwork are very positive, in particular given the program is early-stage and encompasses only initial sighter testing with no optimisation of reagent additions. The high extractions achieved in this preliminary work provide us with validation of the ongoing exploration program and these results give Firetail a solid foundation for our continued activities aimed at proving up this asset.

“Firetail’s strategy with the Mt Slopeaway Project include increasing the classification and size of the existing 4Mt mineral resource. The extension of our exploration permit gives us the opportunity to continue advancing our exploration work on site, and we appreciate the support of the Queensland Government in exploring for these Critical Minerals.

“I am delighted with the progress made at Mt Slopeaway and look forward to bringing news to our shareholders as we progress through our milestones.”

Preliminary Metallurgical Testwork and Discussion of Results

Earlier this year, four composite samples representing various lithologies (i.e., ferricrete, ferricrete silica, serpentenite, and laterite) of the Mt Slopeaway resource were analysed by semi-quantitative x-ray diffraction and tested by Strategic Metallurgy Pty Ltd in Perth, using commercial Ambient, Heated and High-Pressure Leach (HPAL) techniques. In all cases, high nickel extractions (up to 97%) were achieved using conventional pressure leaching, with cobalt extractions also high overall but somewhat more variable ranging from 58% to 96%.

Under ambient leach conditions, demonstrated amenability was achieved for only the ferricrete and serpentinite samples. Although nickel recovery was low (39% and 25% respectively after 24h), kinetic graphs indicate this will increase with additional time, and also suggests that these particular samples may be amenable to in-situ or heap leach extraction methods. It must be noted that few laterites are readily leached under atmospheric conditions, with atmospheric leaching most suited to saprolitic ore types.

Heated Leach tests were performed at 90°C in agitated tanks with relatively high sulfuric acid dosages (around 1000 g acid/kg feed solids) for a 24 hour run. Hot atmospheric leaching resulted in demonstrated amenability for all samples (Table 1), with excellent recovery from ferricrete and serpentinite samples (88% and 92% Ni respectively after 24h), whereas Ni recovery from laterite and ferricrete silica was somewhat more moderate at ~70%. Leaching kinetics indicated that Ni showed fast initial leaching in the serpentine and ferricrete samples, with slower uptrends for laterite and ferricrete silica. Cobalt showed significantly faster initial leaching in the serpentinite, with a gradual uptrend for all samples after that. The slowest leaching for cobalt was found in the ferricrete silica.

Table 1: Extractions in Heated Leach (90°C)

High pressure acid leach (HPAL) tests were performed at 250°C in an agitated 2.6 L lab-scale autoclave. Different acid dosages were used for each of the composites, with dosages selected to ensure sufficient acid would be left for leaching after the acid-consuming components of the ore (e.g. magnesium, aluminium) reacted. Acid dosages ranged from 300 g/kg dry feed for Ferricrete Silica to 860 g/kg dry feed for Serpentinite. The HPAL tests were each carried out for a 2 hour run.

HPAL tests resulted in Ni recoveries of >96% after 2h for ferricrete, laterite and serpentinite samples, with Ni recovery of ~82% from ferricrete silica (Table 2). Nickel extraction was highest for ferricrete (97%), laterite and serpentinite (both 96%) with ferricrete silica lower at 82%.

Cobalt extraction was highest for laterite (96%) and ferricrete (95%), still high for ferricrete silica (87%) but significantly lower for serpentinite (58%). The low Co head grade in serpentinite (0.03% vs. 0.06- 0.28% for the other composites) mitigates the impact of lower cobalt extraction. The lower extraction could be the result of some cobalt being present as "background grade" in an unleached mineral, which could be more obvious for the serpentinite given the lower Co head grade.

Manganese extraction was also high, ranging from 53 to 96% at head grades of 0.2 to 1.86%. The significant amount of Mn present in the leach liquor is relevant as Mn precipitates in the same range of pH as Ni and Co. Thus, processing flowsheets involving the production of a mixed hydroxide precipitate (MHP) would require a Mn removal stage ahead of MHP precipitation to avoid contaminating the MHP product.

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