Great Northern Minerals Ltd (ASX: GNM) — Major Land Expansion Strengthens Iron Butte Gold-Silver Project in Nevada

26 May 2027

Price Sensitive Announcement $

Highlights:

• GNM has filed field staking applications for an additional 46 lode claims covering approximately 950 acres, materially expanding the overall footprint of the Iron Butte Gold-Silver Project within a highly prospective mineralised corridor in Lander County, Nevada
• The two newly acquired claim areas — Caetano Rim (35 claims) and Valmy (11 claims) — display comparable geology, alteration styles and geochemical signatures to known mineralised zones already confirmed at Iron Butte
• Historical soil sampling across the new claim areas returned strong gold-silver mineralisation at surface with assays up to 179ppb gold and 3.8ppm silver over strike lengths of up to 1km, providing a strong foundation for rapid target generation
• Caetano Rim is situated along the rim of the Caetano Caldera — host to several significant gold deposits including the renowned Cortez Gold deposit — within a structurally complex faulted setting analogous to Iron Butte’s existing mineralised zones
• Valmy is hosted by Ordovician-aged geology and northeast-trending faults, a similar geological setting to multiple gold deposits surrounding the Caetano Caldera within the broader Cortez Mining District
• A geophysical review is well advanced and will be instrumental in defining and prioritising drill targets ahead of permitting and contractor engagement
• A maiden Inferred JORC-compliant Mineral Resource for Iron Butte is expected imminently, representing a significant de-risking milestone for the project

Overview:

Great Northern Minerals has materially expanded its Iron Butte Gold-Silver Project in Nevada’s Battle Mountain–Cortez Gold Trend — one of the state’s most prolific gold corridors — through the staking of 46 additional lode mining claims across two new areas totalling approximately 950 acres.

The Caetano Rim area, comprising 35 claims immediately north-northwest of the existing Iron Butte claims, sits along the rim of the Caetano Caldera within a structurally complex zone of faulting in the Caetano Tuff — the primary volcanic host rock for the Iron Butte deposit. Historical soil geochemistry has returned values up to 174ppb Au and 3.8ppm silver over an 850m by 300m area, with the key contact to underlying sedimentary units preserved at varying depths. Importantly, no rock sampling has been completed here, leaving significant upside for GNM’s upcoming surface program.

The Valmy area, comprising 11 claims located 3.6km southeast of the existing project, is hosted by Ordovician-aged Valmy group rocks and associated northeast-trending faults — a geological setting analogous to several gold deposits within the Cortez Mining District. Soil geochemistry has returned anomalies of up to 69ppb Au and 1.4ppm silver over a 1km by 300m corridor, also untouched by rock sampling to date.

Both new areas will be integrated into GNM’s broader exploration strategy, with surface sampling prioritised once the ongoing geophysical review is complete. In parallel, the Company is advancing permitting and contractor engagement ahead of its maiden drilling campaign, while data compilation supporting a maiden Inferred JORC-compliant Mineral Resource for Iron Butte is now complete — with the resource estimate expected imminently.

Company Notes:

Non-Executive Chairman, Eddie King, commented: “The expansion of the landholding at Iron Butte
represents a strategic step in consolidating a highly prospective mineralised system. The newly staked
claims cover extensions of the same favourable geology and structural setting that hosts the known
gold–silver mineralisation at Iron Butte, significantly increasing the scale and upside potential of the
project.

Our recent work has highlighted that mineralisation is not confined to the existing resource area, with
encouraging geochemical signatures and alteration observed across the broader project footprint. The
addition of these claims positions us to systematically explore these extensions and generate new drill
targets, while continuing to advance toward a maiden Inferred JORC-compliant Mineral Resource.”

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