Ardea Resources Quarterly Update - Q3 2025

• Sumitomo Metal Mining and Mitsubishi Corporation earned 17.5% equity in Kalgoorlie Nickel Pty Ltd after investing A$49.25 million, with A$30 million remaining in committed DFS funding
• Heritage Agreement signed with Marlinyu Ghoorlie Native Title Claimant Group covering survey protocols and clearance procedures
• Goongarrie South drilling returned intercepts of 34 metres at 1.75% nickel from 12 metres and 26 metres at 1.48% nickel from 22 metres depth
• Cash position of A$15.5 million with no debt as at 30 September 2025
• DFS completion rescheduled to mid-first half of 2026 from original December 2025 target due to cumulative delays across workstreams

Ardea Resources (ASX:ARL) is a mineral exploration company operating in Western Australia, focused on developing the Kalgoorlie Nickel Project. The company reports a total resource of 854 million tonnes at 0.71% nickel and 0.045% cobalt, containing 6.1 million tonnes of nickel and 386,000 tonnes of cobalt. The Goongarrie Hub, comprising 584 million tonnes of this resource, is being developed through an incorporated joint venture with Sumitomo Metal Mining and Mitsubishi Corporation. Ardea holds 82.5% of Kalgoorlie Nickel Pty Ltd, with the consortium able to increase its stake to 50% following a positive Final Investment Decision.

DFS Progress and Timeline Update

The September quarter saw completion of major fieldwork and testwork programmes for the Definitive Feasibility Study at the Goongarrie Hub. The geology team advanced Mineral Resource Estimate model updates to support mining schedule optimisation, with the Big Four resource model completed and delivered to mining consultants. Metallurgical testwork programmes have largely concluded, with the team now focusing on results processing, model refinement, and drafting DFS report chapters.

Process engineering work progressed during the quarter, with all process flow diagrams and piping and instrumentation diagrams approved for study purposes. The process plant three-dimensional model was completed, and the Process Design Criteria documentation reached substantial completion. Engineering consultant Ausenco's DFS workstreams are scheduled for completion in the December quarter. The project recorded zero lost-time injuries during the period.

The company revised its DFS completion timeline to mid-first half of calendar year 2026 from the original December 2025 target.

Managing Director Andrew Penkethman stated:

"The September 2025 Quarter has seen consistent and meaningful progress across all facets of the Kalgoorlie Nickel Project - Goongarrie Hub. With major drilling and metallurgical testwork programmes now largely complete, the KNPL team is focused on interpreting results, refining models, completing detailed engineering design and drafting the initial chapters of the Definitive Feasibility Study." 

Consortium Equity Earn-In and Heritage Agreement

Sumitomo Metal Mining and Mitsubishi Corporation earned a 17.5% equity interest in Kalgoorlie Nickel Pty Ltd during the quarter after spending A$49.25 million on DFS activities, representing 50% of the consortium's A$98.5 million committed funding. Under the transaction structure, the consortium can increase ownership to 35% upon full DFS spend completion, with an option to acquire up to 50% following a positive Final Investment Decision.

A Heritage Agreement was executed with the Marlinyu Ghoorlie Native Title Claimant Group during the quarter. The agreement establishes protocols for heritage surveys, site protection activities, and clearance procedures for project activities. Following this agreement, Kalgoorlie Nickel Pty Ltd will work with the group to negotiate a Native Title Agreement.

Ardea and consortium partners held regular technical meetings at the West Perth offices during the quarter. The company, with strategic adviser ICA Partners, continued discussions regarding post-DFS funding strategies.

Managing Director Andrew Penkethman stated:

"Collaboration between Ardea, SMM and MC remains a strength of the Project, ensuring that the full technical and commercial expertise of all partners is applied to deliver a world-class outcome."

Goongarrie South Drilling and Resource Updates

The reverse circulation infill drilling programme at Goongarrie South returned results including 34 metres at 1.75% nickel from 12 metres depth, 26 metres at 1.48% nickel from 22 metres, and 26 metres at 1.30% nickel from 14 metres. The company reports this as the highest-grade nickel-cobalt deposit within the Goongarrie Hub, dominated by goethite mineralisation. The increased drill density supports potential upgrades of Mineral Resource classification to Measured category and additional Proven Ore Reserves for the DFS.

The drilling programme, which extended deeper than historical programmes, identified previously untested Mineralised Neutraliser at Goongarrie South. The company states this material may support deeper pit designs in the DFS and could provide operating and capital cost benefits during early development stages, subject to confirmation through detailed Mineral Resource Estimate updates and bench-scale metallurgy research currently underway.

Resource model updates progressed during the quarter, with density and moisture data from diamond drilling finalised and provided to geological consultants. The Big Four resource model completion enabled mining consultants to commence updated mine plans and schedules. Geological models for Goongarrie Hill and Highway advanced, whilst initial interpretations of Goongarrie South results are underway to support updated geological models for the deposit.

Upcoming Activities

During the December quarter, the geology team will continue resource block model updates for deposits in the initial mining plan. DFS report drafting will continue, particularly for processing and non-process infrastructure sections. Additional hydrogeological work is scheduled, including water bore drilling and test pumping.

Environmental baseline surveys will continue into the spring season, with heritage surveys shifting to the planned Goongarrie village and process plant sites. The company will continue engagement with the Marlinyu Ghoorlie Native Title Claimant Group towards a Native Title Agreement. The project's Major Project Status was renewed in October 2025 for a three-year term until October 2028. As at 30 September 2025, the company held A$15.5 million cash with no debt, alongside A$30 million in remaining consortium funding for DFS completion. 

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