Perseus Mining Approves CMA Underground Project Extending Yaouré Mine Life to 2035

• Perseus Mining has taken a Final Investment Decision to develop the CMA underground project at its Yaouré Gold Mine in Côte d'Ivoire.
• The CMA underground project, combined with open pit sources, is expected to extend Yaouré's mine life to at least 2035 based on current reserves.
• Underground mining will allow further utilization of the high-grade CMA deposit, with underground ore representing ~20% of total tonnage mined once operations reach steady state.
• The project is on track in terms of timeline and budget, with major capital expenditures planned for FY26 and FY27 as underground development work gets underway.
• Perseus Mining reaffirmed its plan to continue producing 500,000-600,000 ounces of gold per year across its portfolio at a cash margin of at least $500 per ounce.

Perseus Mining Limited is a multi-mine West African gold producer, developer and explorer, operating three gold mines in Côte d'Ivoire and Ghana. The company's flagship operation is the Yaouré Gold Mine in Côte d'Ivoire, which achieved commercial production in 2020. Perseus is focused on generating value for all stakeholders through responsible mining activities and organic growth opportunities.

CMA Underground Project Approved

Perseus Mining announced it has taken a Final Investment Decision (FID) to develop the CMA underground project at its Yaouré Gold Mine in Côte d'Ivoire. The decision follows in-principle approval from the Ivorian government and marks a key milestone in the growth of Perseus's flagship operation.

The CMA underground project is expected to extend Yaouré's life of mine to at least 2035, based on current Ore Reserves. It will be the first modern underground mining operation in Côte d'Ivoire. As part of the FID, Perseus appointed Australian specialist underground mining contractor Byrnecut to lead development and operation of the project. Byrnecut is expected to mobilize to site by April 2025.

High-Grade Deposit Adds Ounces

The CMA deposit has proved a reliable foundation for Yaouré's success to date. Moving to underground mining will allow Perseus to further exploit this high-grade ore source. Based on current resources, underground material will represent about 20% of total ore mined at Yaouré once the operation reaches steady state production of 700,000-770,000 tonnes per annum.

Underground reserves currently stand at 4.9Mt at 3.51g/t gold for 560,000 ounces, with significant exploration potential at depth. Average all-in underground mining costs are estimated at about US$75 per tonne, with the underground operation expected to contribute nearly 50% of Yaouré's total gold output over its mine life.

"The move to underground operations allows further utilisation of the CMA deposit – which has proved to be a reliable foundation of the Yaouré operation to date," said Perseus Managing Director and CEO Jeff Quartermaine. "At steady state production rates, it is planned that underground ore will represent approximately 20% of the tonnes of ore mined on the site from both open cut and underground operations."

Ivorian Workforce Training

As Yaouré will be Côte d'Ivoire's first mechanized underground mine, an important focus for Perseus and Byrnecut will be training the local workforce in modern underground mining methods and safety protocols. Byrnecut brings extensive underground experience in West Africa through its operations in Ghana, Burkina Faso, and Mali.

"While this represents a new phase for the Ivorian mining sector, members of our technical team have considerable individual experience operating mines in underground settings throughout the world, with a strong commitment to human and environmental safety as well as training of our Ivorian workforce," said Quartermaine.

Project Advancing on Schedule

Preparations for the start of underground mining are well underway, with key infrastructure upgrades and personnel recruitment in progress. Initial work on the mine portal is expected to begin in Q1 FY26 after completion of open pit mining in the area. The CMA underground project is on track in terms of both budget and schedule.

Total approved capital expenditure for the project is $124.6 million, the bulk of which will be incurred in FY26 and FY27 as underground development ramps up. Perseus has already invested $4.1 million in early works including camp upgrades, equipment orders and mine services in preparation for underground contractor mobilization.

"The project remains on track with its planned timelines and budgetary requirements, and we look forward to providing further updates as development progresses," Quartermaine said.

Updated Life of Mine Plan

Perseus intends to publish updated Life of Mine production and cost forecasts for the entire company in Q1 FY26, incorporating the CMA underground project at Yaouré and the pending Nyanzaga Gold Mine development in Tanzania. This consolidated plan is expected to confirm Perseus's target of producing 500,000-600,000 ounces of gold per year across its operations at a cash margin of not less than $500 per ounce.

Mineral Resources and Ore Reserves

Measured and Indicated Mineral Resources at Yaouré totaled 55.6Mt at 1.52g/t gold for 2.71 million contained ounces. This includes an underground resource of 7.4Mt at 4.16g/t for 996,000 ounces. Inferred Resources add a further 17.4Mt at 1.7g/t for 926,000 ounces, including 514,000 ounces in the underground resource category.

Proved and Probable Ore Reserves total 35.2Mt at 1.53g/t for 1.73 million contained ounces. Open pit reserves contribute 1.08 million ounces with underground reserves adding 560,000 ounces at an average grade of 3.51g/t gold.

For Investors

The Final Investment Decision on the Yaouré CMA underground project marks an important growth milestone for Perseus Mining. By extending the life of the company's flagship operation to at least 2035, the project underpins Perseus's long-term production and cash flow outlook.

Underground development will allow Perseus to fully exploit the high-grade potential of the CMA deposit as open pit operations wind down. With the bulk of capital spending to come in FY26 and FY27, the company is well positioned to maintain its targeted production and cost profile as a multi-mine West African gold producer.

Continued exploration success at Yaouré, both from near-mine drilling and regional programs, bodes well for further resource growth and mine life extensions. As underground development progresses, Perseus is positioned to generate significant value for shareholders through organic growth at Yaouré and across its portfolio.