PRU increases Nyanzaga Project Ore Reserves to 4.0Moz

Perth, WA, Feb. 20, 2026 (GLOBE NEWSWIRE) -- PERSEUS MINING INCREASES NYANZAGA GOLD PROJECT ORE RESERVES TO 4.0 Moz

Overview

Perth, Western Australia/ February 20, 2026/ Perseus Mining Limited (ASX/TSX: PRU) is pleased to announce an updated Ore Reserve of 4.0 Moz for the Nyanzaga Gold Project (NGP) in Tanzania (Table 1). This represents a 73% increase to the 2.3 Moz Ore Reserve reported in April 2025 as part of the updated NGP Feasibility Study (FS). A summary of the release is included below. For the full release including JORC tables, please refer to www.perseusmining.com, www.asx.com.au or www.sedarplus.ca.

Mine life for the Nyanzaga Gold Project is extended to 16 years, including 14 years of production at greater than 200 koz/a. An increased Perseus Ore Reserve for Nyanzaga is based on a further cutback to a large scale, open-pit mining operation as outlined in the NGP FS.

Table 1: Nyanzaga Gold Project Ore Reserves^1,2,3,4,5,6

Notes for Table 1:

1        Based on November 2025 Mineral Resource estimate

2        Based on February 2026 Ore Reserve estimate

3        Pit designs are based on US$2,300/oz gold metal price

4        Variable gold grade cut-offs for each material type, ranging from 0.3 g/t to 0.4 g/t

5        Inferred Mineral Resource is considered as waste for optimisation purposes

6        Rounding of numbers to appropriate precision may have resulted in apparent inconsistencies

This increase is underpinned by approximately 82,700 m of reverse circulation and diamond drilling across the Tusker and Kilimani deposit areas completed since Perseus acquired the Project in May 2024. This drilling was aimed at infill and extension of the mineralisation, and the conversion of Mineral Resources from the Inferred to Indicated category. In parallel, Perseus has continued to refine the underlying technical assessments via various studies supporting the NGP Ore Reserve update. The contributions of these activities to the updated Ore Reserve are presented in Figure 1.

Figure 1: Nyanzaga Gold Project Ore Reserve Changes – April 2025 to February 2026

Key metrics associated with the NGP include the following:

Production & Cost Metrics (100% basis):

1. Total gold production over a 16-year is currently estimated to be 3.5 Moz based on a JORC 2012 Probable Ore Reserve of 90.9 Mt @ 1.38 g/t gold for 4.0 Moz.
2. Gold production exceeds 200,000 ounces of gold per annum from FY28 to FY41.

Applying Perseus’s assumed long-term gold price of US$3,000/oz, the NGP’s investment metrics are updated to:

1. Over the life of the mine, the estimated average All-In Site Cost (AISC) is US$1,621/oz.
2. Undiscounted free cashflow post-tax of US$2,651 million
3. Net Present Value (NPV_10%) of US$864 million post-tax.
4. Internal Rate of Return (IRR) of 28.8% post-tax

Note: Perseus owns an 80% contributing interest in the NGP together with the Government of Tanzania who owns a 20% non-contributing interest.

This announcement was approved for release by the Managing Director & CEO, Craig Jones.

Mineral Resources

The NGP Mineral Resource estimate consists of two discrete but adjacent deposits: Tusker and Kilimani. Following approximately 82,700 m of drilling across both deposit areas, Perseus has prepared a revised Mineral Resource estimate for the NGP. The combined M&I Mineral Resource for the NGP is estimated at 110.4 Mt grading 1.33 g/t Au, containing 4.7 Moz of gold. A further 6.5 Mt of material grading 1.6 g/t Au, containing 343 koz of gold is classified as Inferred Mineral Resources (Table 2).

As a result of pit design parameters such as ramp configuration and batter arrangements, there are approximately 500 oz (0.01%) of ore reported in the Ore Reserve that is not included in the Mineral Resource. This is not considered material, and no adjustment has been made to the figures reported to account for this.

Table 2: NGP Mineral Resources^1,2,3,4,5,6

Notes for Table 2:

1        Based on November 2025 Mineral Resource estimate

2        0.25 g/t gold cut-off applied to in-situ open pit material

3        In-situ open pit resources are constrained to US$2,700/oz pit shells

4        Rounding of numbers to appropriate precision may result in summary inconsistencies

5        Mineral Resources are inclusive of Ore Reserves with the exception of approx. 500 oz reported as Ore Reserves but excluded from Mineral Resources

6        Mineral Resources are reported on a 100% basis

Mineral Resource Material Information

Mineral Tenement and Land Tenure Status

The NGP consists of one Special Mining Lease (SML), six granted prospecting licences, and one prospecting licence application (Table 3). Through its subsidiary, Nyanzaga Mining Company Limited (NMCL), Perseus holds an 80% interest in Sotta Mining Corporation (SMCL). The SML was granted on 13 December 2021 to SMCL for an initial period of 15 years, with extensions permissible under application before the final year. The Treasury Registrar holds the 20% free carried interest of the Government of Tanzania in accordance with the Mining Act.

Table 3: NGP tenement summary

Ore Reserves

The Ore Reserve estimate for the NGP is based on the new Mineral Resource estimate. Modifying factors remain materially consistent with those resulting from the April 2025 Perseus Nyanzaga Feasibility Study Update. The Ore Reserve is classified as Probable in accordance with the JORC Code (2012), corresponding to the Indicated Mineral Resource classification and considering other factors where relevant. The deposit’s geological model is well constrained. The Ore Reserve classification is considered appropriate given the nature of the deposit, the moderate grade variability, drilling density, structural complexity, and confidence in input parameters. It is therefore considered appropriate to use Indicated Mineral Resources as a basis for Probable Ore Reserves.

The Probable Ore Reserve for the NGP is estimated as 90.9 Mt, grading 1.38 g/t Au and containing 4.0 Moz of gold (Table 4). The Ore Reserve pit design is presented in Figure 7.

Table 4: Nyanzaga Gold Project Ore Reserves^1,2,3,4,5,6

Notes for Table 4:

1        Based on November 2025 Mineral Resource estimate

2        Based on February 2026 Ore Reserve estimate

3        Pit designs are based on US$2,300/oz gold metal price

4        Variable gold grade cut-offs for each material type, ranging from 0.3 g/t to 0.4 g/t

5        Inferred Mineral Resource is considered as waste for optimisation purposes

6        Rounding of numbers to appropriate precision may have resulted in apparent inconsistencies

Technical Disclosure:

All Ore Reserves and Mineral Resources were calculated as of 20 February 2026 and have been prepared in accordance with the standards set out in the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves dated December 2012 (the JORC Code) and in accordance with National Instrument 43-101 of the Canadian Securities Administrators (NI 43-101). The JORC Code is the accepted reporting standard for the Australian Stock Exchange Limited (ASX).

The definitions of Ore Reserves and Mineral Resources as set forth in the JORC Code (2012) have been reconciled to the definitions set forth in the CIM Definition Standards. If the Mineral Reserves and Mineral Resources were estimated in accordance with the definitions in the JORC Code, there would be no substantive difference in such Mineral Reserves and Mineral Resources.

Competent Person Statement:

All production targets referred to in this report are underpinned by estimated Ore Reserves which have been prepared by Competent Persons in accordance with the requirements of the JORC Code.

The information in this report that relate to Mineral Resources for the Nyanzaga Gold Project is based on, and fairly represents, information and supporting documentation prepared by Mr Daniel Saunders, a Competent Person, a full-time employee of Perseus Mining and Fellow of The Australasian Institute of Mining and Metallurgy. Mr Saunders has sufficient experience, which is relevant to the style of mineralisation and type of deposit under consideration and to the activity being undertaken, to qualify as a Competent Person as defined in the 2012 Edition of the “Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves” and to qualify as a Qualified Person under National Instrument 43-101 – Standards of Disclosure for Mineral Projects (NI 43-101). Mr Saunders consents to the inclusion in the report of the matters based on his information in the form and context in which it appears.

The information in this report that relates to Ore Reserves for the Nyanzaga Gold Project is based on information compiled by Mr Adrian Ralph, a Competent Person who is a Fellow of The Australasian Institute of Mining and Metallurgy. Mr Ralph is a full-time employee of Perseus Mining. Mr Ralph has sufficient experience which is relevant to the style of mineralisation and type of deposit under consideration and to the activities which he is undertaking to qualify as a Competent Person as defined in the 2012 Edition of the “Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves” and a Qualified Person as defined in NI 43-101. Mr Ralph consents to the inclusion in this report of the matters based on his information in the form and context in which it appears.

Caution Regarding Forward Looking Information:

This report contains forward-looking information which is based on the assumptions, estimates, analysis and opinions of management made in light of its experience and its perception of trends, current conditions and expected developments, as well as other factors that management of the Company believes to be relevant and reasonable in the circumstances at the date that such statements are made, but which may prove to be incorrect. Assumptions have been made by the Company regarding, among other things: the price of gold, continuing commercial production at the Yaouré Gold Mine, the Edikan Gold Mine and the Sissingué Gold Mine without any major disruption, development of a mine at Nyanzaga, the receipt of required governmental approvals, the accuracy of capital and operating cost estimates, the ability of the Company to operate in a safe, efficient and effective manner and the ability of the Company to obtain financing as and when required and on reasonable terms. Readers are cautioned that the foregoing list is not exhaustive of all factors and assumptions which may have been used by the Company. Although management believes that the assumptions made by the Company and the expectations represented by such information are reasonable, there can be no assurance that the forward-looking information will prove to be accurate. Forward-looking information involves known and unknown risks, uncertainties, and other factors which may cause the actual results, performance or achievements of the Company to be materially different from any anticipated future results, performance or achievements expressed or implied by such forward-looking information. Such factors include, among others, the actual market price of gold, the actual results of current exploration, the actual results of future exploration, changes in project parameters as plans continue to be evaluated, as well as those factors disclosed in the Company's publicly filed documents. Readers should not place undue reliance on forward-looking information. Perseus does not undertake to update any forward-looking information, except in accordance with applicable securities laws.

Attachment

• Nyanzaga_Ore_Reserve_Update_Lean_20260219_Final