Great Northern Minerals Reports Maiden 480,000 Oz Gold Resource at Iron Butte Nevada

Maiden Resource Establishes Iron Butte as Significant Nevada Deposit

Great Northern Minerals Limited (ASX:GNM) has announced a maiden Inferred Mineral Resource Estimate (MRE) for its Iron Butte Gold-Silver Project in Lander County, Nevada. The estimate, prepared by ERM Australia Consultants under the JORC Code (2012), quantifies 37.85 million tonnes grading 0.4 g/t gold and 6 g/t silver, equating to 480,000 ounces of gold and 6.7 million ounces of silver. An additional 19.25 million tonnes grading 8 g/t silver adds 4.8 million ounces of silver, bringing the total silver resource to 11.5 million ounces.

This maiden resource positions Iron Butte among the larger undeveloped gold-silver deposits in Nevada’s prolific Battle Mountain-Cortez Mining District, a globally renowned gold corridor that hosts major mines such as Marigold (SSR Mining), Phoenix (Nevada Gold Mines), and Florida Canyon (Integra Resources). The deposit’s tonnage and grade profile align with bulk-tonnage heap-leach operations typical of the region, highlighting its commercial potential subject to further studies.

Resource Open in All Directions with Exploration Upside

The resource remains open along strike and at depth, with geological interpretations indicating significant Carlin-style gold and silver mineralisation beneath the current MRE footprint. Notably, drill intersections such as 1.5m at 13.5 g/t gold and 11.5 g/t silver from 405.4m depth underscore the deposit’s upside potential beyond the near-surface oxide zone.

Great Northern Minerals is advancing a geophysical reinterpretation of the expanded project area to refine drill targets. The company plans to commence its maiden drilling program in Q3 2026, aiming to grow the resource through step-out and depth drilling and to test other promising targets within its claim boundaries. With $3.9 million in cash, the company is fully funded for this next phase.

Robust Geological Foundation and Resource Modelling

The Iron Butte deposit is hosted within rhyolitic volcanic rocks and footwall shale units, forming an epithermal system with significant oxide mineralisation near surface. The resource model incorporates 146 reverse circulation and 2 diamond drill holes totaling over 23,000 metres, with mineralisation domains interpreted separately for gold and silver.

ERM’s resource estimation used ordinary kriging on a 50m by 50m by 5m block model, validated through multiple statistical checks. The Mineral Resource is classified as Inferred, reflecting current confidence levels given drill spacing and data quality. Bulk density values were assumed based on analogous deposits, as no density measurements have yet been collected from the project.

Next Steps Include Metallurgical Review and Permitting

Great Northern Minerals intends to review historical metallurgical test work and conduct additional testing to incorporate silver into a gold equivalent resource estimate. Planning and permitting activities are underway to facilitate drilling, with multiple exploration targets already identified to underpin the maiden campaign.

Non-Executive Chairman Eddie King emphasised the milestone nature of the resource estimate, describing it as a foundation for growth and a validation of Iron Butte’s development potential within a world-class mining jurisdiction. The company’s strategic positioning and cash reserves provide a solid platform for advancing the project towards potential mine development.