Revised mine plan adds approximately 3 million tons of mineralized material to be mined between 2027 and 2029; Nuton LLC to provide a US$8 million payment to Gunnison. The optimized plan supports operational continuity, preserves critical workforce capabilities, and advances the Johnson Camp demonstration project.

Gunnison Copper Corp. (TSX: GCU) (OTCQB: GCUMF) (FSE: 3XS0) is pleased to announce that it has reached an agreement with Nuton LLC, a Rio Tinto venture, to revise and optimize the Stage 2 mine plan at the Johnson Camp Mine in southeast Arizona, adding approximately 3 million tons of mineralized material to the mine plan and further enhancing the value of the project.

Under the revised mine plan, the additional tons of mineralized material are expected to be mined within the planned demonstration period between 2027 and 2029, enhancing project value while maintaining the existing Stage 2 schedule.

Related to the mining activities, Nuton has agreed to make a US$8 million payment to Gunnison. The Company expects to receive the payment in Q4 2026. The payment reflects the value created through the optimized mine plan and the parties’ continued commitment to advancing the Johnson Camp demonstration project.

The revised mine plan is expected to preserve Gunnison’s critical operational capabilities and experienced workforce throughout the demonstration period, supporting operational continuity and future project opportunities.

“The optimized mine plan adds approximately 3 million tons of mineralized material and further enhances the value of Johnson Camp,” said Craig Hallworth, President and CEO of Gunnison Copper. “The additional material supports continued operations, preserves critical workforce and technical capabilities, strengthens the long-term outlook for the project, and advances our mission to reliably supply pure American copper from Southern Arizona.”

The Company also announces it has elected not to proceed with claiming the Department of Energy 48C Tax Credits as conditionally awarded to the Company in January 10, 2025 as part of the 48C selection process. Gunnison will continue to evaluate U.S. Federal tax incentive opportunities to maximize value and support the long-term interests of the company.

ABOUT GUNNISON COPPER

Gunnison Copper Corp. is a multi-asset pure-play copper developer and producer that controls the Cochise Mining District (the district), containing 12 known deposits within an 8 km economic radius, in the Southern Arizona Copper Belt.

Its flagship asset, the Gunnison Copper Project, has a main pit Measured and Indicated Mineral Resource containing over 846 million tons with a total copper grade of 0.33% containing 5.19 billion pounds of copper (Measured Mineral Resource of 192 million tons at 0.37% containing 1.42 billion pounds of copper and Indicated Mineral Resource of 655 million tons at 0.31% containing 3.77 billion pounds of copper).

The Strong & Harris satellite deposit, located approximately 1.9 miles from the Gunnison processing facilities, is also included in the mine plan and hosts an Inferred Mineral Resource of 76 million tons grading 0.49% total copper (0.32% CuOx) at a 0.07% cutoff, 0.56% zinc and 0.12 oz/ton silver, containing approximately 740 million pounds of copper, including 483 million pounds of oxide copper, as well as zinc (856 million pounds) and silver (9.0 million ounces).

A preliminary economic assessment was completed in March 2026 for the Gunnison Project yielding robust economics including an NPV8% of $2 billion, IRR of 23%, and payback period of 3.9 years. It is being developed as a conventional operation with open pit mining, heap leach, and SX/EW refinery to produce finished copper cathode on-site with direct rail link. The PEA is preliminary in nature and includes Inferred Mineral Resources that are considered too speculative geologically to have the economic considerations applied to them that would enable them to be categorized as mineral reserves. There is no certainty that the conclusions reached in the PEA will be realized. Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability.

In addition, Gunnison’s Johnson Camp Asset, which is now in production, is fully funded by Nuton LLC, a Rio Tinto Venture, with a production capacity of up to 25 million lbs of finished copper cathode annually.

Other significant deposits controlled by Gunnison in the district, with potential to be economic satellite feeder deposits for Gunnison Project infrastructure, include South Star, and eight other deposits.

For more information on the Company, please visit our website at www.GunnisonCopper.com.

For additional information on the Gunnison Project, please refer to the technical report titled “Gunnison Project NI 43-101 Technical Report, Preliminary Economic Assessment, Cochise County, Arizona, USA” with an effective date of March 18, 2026 filed on SEDAR+ at www.sedarplus.ca.

For additional information on the Johnson Camp Mine, please refer to the technical report titled “Johnson Camp Mine NI 43-101 Technical Report, Cochise County, Arizona, USA” with an effective date of March 18, 2026 filed on SEDAR+ at www.sedarplus.ca.

Dr. Roland Goodgame, Senior VP of Project Development of the Company is a Qualified Person as defined by NI 43-101. Dr. Goodgame has reviewed and approved the technical information contained in this news release.