Mr. Julian Vickers reports

NORTHMIN ANNOUNCES POSITIVE METALLURGICAL TEST WORK RESULTS FROM THE MINERAL RESOURCES AT TYNAGH

Northmin Corp. has released positive metallurgical test results on material from the West Pond tailings resource at its 100-per-cent-owned Tynagh project, Republic of Ireland.

Highlights:

• Loop Hydrometallurgy Operations Pty. Ltd. was engaged for a tailings retreatment scoping study.
• Testwork was conducted on a representative sample of material from the west tailings pond (a National Instrument 43-101-compliant tailings resource).
• High levels of metals leaching were achieved; silver (93 per cent), zinc (97 per cent), lead (89 per cent) and copper (81 per cent).
• The testwork also demonstrated that leached metals can be recovered from solution to produce saleable products.
• The flowsheet is based on tank leaching at less than 100 degrees Celsius (at atmospheric pressure) using an aqueous solution of simple salts.
• During leaching, sulphide minerals in the tailings material were oxidized to provide acidity for metals leaching; this simplifies the process flow sheet, and can reduce (or eliminate) the requirement for reagent acid.
• The closed-system process has no noxious gaseous emissions or liquid effluents and the solid waste residue is benign.

Julian Vickers, chief executive officer, stated: "The results from this initial study by Loop Hydrometallurgy in Australia are very encouraging and potentially transformative for the surface silver project at Tynagh. The recoveries of silver are excellent at 93 per cent and the high recoveries of other metals will provide significant additional revenue. The operating costs appear favourable and suggest potential for high operating margins from the project (subject to confirmation by further testwork and economic studies). Furthermore, the safe recovery of metals from waste material to valuable metal products provides a close fit to the government's vision of a circular economy. With these positive results in hand, we are excited to move forward with further techno economic and environmental studies to rapidly advance the project towards production."

Leach testwork

Northmin prepared a representative bulk sample of material from the West Tailings Pond at Tynagh. Resource drilling samples stored with ALS Laboratories in Ireland were riffle split and composited to form the bulk sample. The bulk sample was then shipped to Loop Hydrometallurgy. Portions of the composite were assayed in duplicate and sent for XRD mineralogy. Results confirmed that contained metal values and mineralogy were representative of the high-grade NI 43-101 compliant surface resources at Tynagh.

The test program comprised seven leach test runs. These covered both sequential "standard" and "enhanced" leach conditions using variations of Loop Hydrometallurgy's processes. The primary objective was to investigate the conditions required to achieve high levels of metals value dissolution. Secondary objectives were to investigate the possibilities for reduced reagent costs and to demonstrate some alternatives for producing saleable metals products.

About Loop Hydrometallurgy operations

Loop Hydrometallurgy operations has developed versatile new technology for the extraction and recovery of base and precious metals from a broad range of mineral resources: concentrates, preconcentrates, ores and tailings. The Halion Loop represents a breakthrough opportunity to unlock value from the broad range of low-grade, polymetallic and/or arsenic-contaminated resources.

With no noxious gas emissions and no liquid effluents, the Halion Loop technology operates at atmospheric pressure and less than 100 degrees Celsius, producing high-purity metal directly at the mine site. Key deleterious mineral species in the source materials are destroyed, eliminating acid mine drainage risks from those resources. The outcomes of the mild process conditions, together with the minimisation of material transport and elimination or long-term risks, collectively minimizes net environmental impact, particularly carbon footprint for metals processing.

Loop Hydrometallurgy's standard Halion Loop leaching process typically utilizes three leach stages, however, leach stage 3 may not be required when strong extraction results are achieved in leach stage 2. The enhanced leach uses more oxidizing conditions to attack sulphides in the feed material.

Testwork results

In the standard leach test runs, the second stage extractions were as shown in the attached table.

It was therefore concluded that a third stage standard leach was not necessary.

In the enhanced leach tests the extractions were as shown in the attached table.

Loop Hydrometallurgy reported that the enhanced leach results were strongly encouraging and support both a simplified process flow sheet and the substantial elimination of the need for reagent acid. The results suggest that optimization of the conditions between tests E2 and E3 could facilitate leaching without the need for significant acid or base additions.

With regard to arsenic, the Halion Loop process rapidly oxidizes and precipitates any contained arsenic in the form or scorodite. Arsenic levels were tracked during the Tynagh testwork and the element was found to be absent in the liquor.

Loop Hydrometallurgy carried out preliminary testwork to confirm the scope for selectivity in metal products. Other standard product options also remain available for consideration, and could be produced instead of, or in tandem with, selective metal products.

Additional information regarding the mineral resource and sampling program is contained in the company's technical report entitled "Evaluation of the Tynagh Tailings Ponds at Tynagh Mine, County Galway, Ireland" (effective date: March 18, 2026) which is available on the company's website and at SEDAR+. The metallurgical test results reported herein are preliminary in nature and additional work will be required to optimize and confirm process performance and product recoveries.

Next steps

Northmin has asked Loop Hydrometallurgy to carry out a study to determine the likely economics of the flowsheet. This will take account of expected revenues, operating costs and capital expenditures. The company will also consider different capacity options to inform the optimal ramp up strategy.

Assuming a positive outcome, the company will carry out further testwork with Loop Hydrometallurgy to confirm the leach performance and operating costs, refine the product strategy and further define the expected economics. Environmental studies will commence in parallel to support the permitting process.

Qualified person

Scientific and technical information in this news release has been prepared by and approved by Dr. Evan Kirby, a consulting metallurgist, director of Northmin and a qualified person (a QP) as defined under NI 43-101.

About Northmin Corp.

Northmin is an exploration and development company advancing the 100-per-cent-owned Tynagh tailings recycling project and the Tynagh copper-zinc brownfield exploration project near Loughrea in County Galway, Ireland. The Tailings Ponds have a NI 43-101 compliant resource consisting of 2.69 Mt (million tonnes) inferred at 21.6 per cent BaO, 49 grams per tonne Ag, 3.56 per cent Zn, 2.68 per cent Pb and 0.23 per cent Cu in the West Pond, 1.26 Mt Indicated at 13.2 per cent BaO, 34 g/t Ag, 3.63 per cent Zn, 2.16 per cent Pb and 0.15 per cent Cu in the East Pond (bottom) and 2.7 Mt indicated at 9.5 per cent BaO, 13 g/t Ag, 1.02 per cent Zn and 0.65 per cent Pb in the East Pond (top). The tailings ponds are accessible and there has been little to no rehabilitation of the site since mine closure in 1982. The company is also assessing the overburden and low-grade ore stockpile on the site and has previously announced high-grade silver results from first-pass sampling. The company also recently announced high-grade copper drill results from below the historic Zn-Pb-Ag mine at Tynagh including 6.4 m grading 4.92 per cent Cu, 0.98 per cent Sb and 62.04 g/t Ag from 149.0 m in hole 3615-26-07.

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