FireFly Metals Ltd (ASX:FFM, TSX:FFM, OTC:MNXMF) has delivered a major step-change at its Green Bay Project, unveiling a substantially larger and higher-quality Mineral Resource supported by a newly defined high-grade core that reshapes the project’s development outlook. FireFly managing director Steve Parsons said, “This outstanding result cements Green Bay’s status as one of the most compelling copper development projects in the world.”
The company has reported a 51% increase in the Green Bay Mineral Resource, which now stands at 1.4 million tonnes of contained copper and 1.1 million ounces of contained gold.
The updated estimate comprises 50.4 million tonnes at 2.0% copper equivalent (CuEq) in the Measured and Indicated (M&I) categories and a further 29.3 million tonnes at 2.5% CuEq in the Inferred category.
This has delivered a significant lift in contained metal, with contained copper in the M&I categories rising to 863,000 tonnes, an increase of 113%, plus 566,000 tonnes in the Inferred category, while contained gold in M&I has increased 174% to 546,000 ounces, with a further 563,000 ounces (+62%) in the Inferred category.
Mineral Resource Estimate for the Green Bay Copper-Gold Project as at November 10, 2025.
Year-on-Year increase in Mineral Resource contained copper equivalent metal since acquisition of the Green Bay Copper-Gold Project in 2023.
A newly defined high-grade core within the Mineral Resource is a key feature of the update.
This zone comprises 8.8 million tonnes at 3.9% CuEq in the M&I categories and 10.9 million tonnes at 3.8% CuEq in the Inferred category.
At the Ming Deposit, the M&I component of the Mineral Resource has grown by 121%, from 21.5 million tonnes to 47.5 million tonnes, and now represents 67% of the total Ming Mineral Resource, providing a stronger basis for upcoming economic studies.
“In just 12 months, we have grown the total Mineral Resource significantly. At the same time, we have established a high-grade core which stands to deliver huge benefits to the project’s development potential, particularly in the initial years of production," Parsons said.
“We will maintain our relentless push to create shareholder value, with eight rigs on the job, to upgrade more of Inferred Mineral Resources to Measured and Indicated and to make new regional discoveries.
“And the appetite for our product is clearly very strong, with several parties signing confidentiality agreements and talks on offtake and funding progressing well.”
Year-on-Year changes between the October 2024 MRE and November 2025 MRE for Tonnes, Grade and Contained Metal. This latest estimate has seen significant year-on-year increases in tonnes, grades and metal content.
Mineralisation open in multiple directions
The mineralisation at Green Bay remains open in multiple directions, including within the high-grade core.
The most distant step-out hole drilled to date on the edge of the resource returned 49 metres at 6.1% CuEq, including 14.3 metres at 13.7% CuEq (reported to the ASX on 16 October 2025), indicating strong potential for further extensions.
Read more: FireFly extends Green Bay copper-gold mineralisation by 650 metres with standout 49-metre intercept
Additional growth potential is supported by a large, high-tenor down-hole electromagnetic (DHEM) conductor that extends well beyond the current Mineral Resource boundary.
Drilling is underway to convert more of the 29.3 million tonnes at 2.5% CuEq currently classified as Inferred into M&I for use in economic studies. A substantial portion of the high-grade core is still in the Inferred category, including intercepts such as hole MUG25-202, which returned 49.0 metres at 6.1% CuEq, underlining the scope for further M&I growth.
Economic studies slated for early 2026
Given the potentially material impact of the recently delineated high-grade mineralisation on project economics, particularly in the early years of production, FireFly plans to release the results of its economic studies in the first half of 2026. Six underground rigs will continue drilling into 2026, while surface rigs will test numerous regional targets generated by recent geophysical surveys and fieldwork.
In parallel, FireFly is progressing discussions with potential offtake partners, export credit agencies and other commercial groups regarding funding options.
Early engagement indicates strong interest in the planned Green Bay concentrate, with several confidentiality agreements already in place.
The company reported A$129.7 million in cash, receivables and liquid investments as at September 30, 2025, providing a solid financial position to support ongoing drilling, studies and commercial activities.
Forward Work Plans
Near-term drilling at the Green Bay Copper-Gold Project will remain focused on three priorities:
- upgrading the Mineral Resource through infill drilling
- growing the Mineral Resource, and
- generating new discoveries from both underground and surface programs.
Key 2024-2025 milestones for the Green Bay Copper-Gold Project. 2026 is indicative.
Six underground rigs will continue to drive Mineral Resource growth at depth through 2026.
Green Bay – Ming Deposit Mineral Resource
The MRE update reflects the success of the low-cost Mineral Resource growth strategy centred on drilling from the 805L exploration drive at the Ming Mine. Development of additional underground drill platforms is in progress, targeting further Mineral Resource additions in 2026.
Underground drilling will prioritise converting the higher-grade 29Mt of Inferred Mineral Resources into the higher-confidence Measured and Indicated (M&I) categories ahead of the Feasibility Study, which is expected to be completed in the second half of 2026 (Figure 5).
Only Measured and Indicated Mineral Resources can be used to define mine economics in a Feasibility Study, making the expansion of the M&I inventory critical to demonstrating the true scale and economic potential of the deposit.