| Gunnison Copper Announces First Copper Production from Johnson Camp Mine 
 America's Newest Copper Producer Delivers Ahead of Schedule
 
 newsfilecorp.com
 
 September 03, 2025 6:30 AM EDT | Source:  Gunnison Copper Corp.
 
 Phoenix, Arizona--(Newsfile Corp. - September 3, 2025) - Gunnison Copper Corp. (TSX: GCU) (OTCQB: GCUMF) (FSE: 3XS0) ("Gunnison" or the "Company") is  thrilled to announce the first production of pure copper cathode from  its fully-operational Johnson Camp Mine ("JCM") in southeast Arizona  commenced in the last week of August 2025, establishing Gunnison as the  newest American Copper Producer.
 
 Following the successful start-up of the solvent extraction (SX) and electrowinning (EW) circuit ( announced August 11, 2025),  copper cathode is now officially in production from run-of-mine (ROM)  ore. Gunnison has achieved this critical milestone ahead of schedule,  producing Made-in-America copper for domestic sales.
 
 "This is  an incredible moment for Gunnison and for U.S. copper supply. To bring  Johnson Camp into production ahead of schedule and with an excellent  health and safety record is an achievement we're extremely proud of,"  states Stephen Twyerould, Chief Executive Officer and President. "Even  more exciting is that we are now producing 100% American-made copper at a  time when our nation needs it most. We extend our gratitude to our  dedicated team, valued stakeholders, and especially Nuton LLC, a Rio  Tinto venture, whose critical support made this possible."
 
 Nuton  is a key strategic and financial partner to Gunnison, supporting the  restart of copper production at JCM. With exclusive rights to deploy its  proprietary leaching technologies, Nuton is enabling a more sustainable  and economically viable path for copper recovery at JCM.
 
 "We  congratulate Gunnison Copper and its dedicated team on this important  milestone and are proud to support the company's efforts in revitalizing  mining in Arizona," added Adam Burley, Nuton's Chief Executive Officer.  "We look forward to first copper production using Nuton technologies  later this year, unlocking copper through innovation and partnership."
 
 Key Highlights of the Johnson Camp Mine Commissioning:
 
 
 First copper production achieved ahead of schedule, firmly establishing Gunnison as America's newest copper producer.Exceptional  safety performance: Commissioning of the ROM copper production circuit  completed without incident, underscoring Gunnison's uncompromising  commitment to health and safety excellence.Critical U.S.  supply: New domestic production strengthens American energy  independence, national defense, and advanced manufacturing capabilities.Partnerships:  Fully funded and supported by Nuton LLC, a Rio Tinto venture, and  awarded US$13.9 million in 48C tax credits from the Department of Energy  ( see Gunnison press release dated January 16, 2025 for additional details).Growth  trajectory: Ramp-up in progress toward the name plate plant capacity of  25 million pounds of finished copper cathode annually.
  
 Figure 1 - Harvesting copper cathode from an electrowinning cell.
 
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 Figure 2- Copper cathode being stripped from stainless steel cathodes.
 
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 Figure 3 - Copper cathode ready for shipment with the Burro pit in the background.
 
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 Figure 4 - The team at work inside the electrowinning plant.
 
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 Figure 5 - Sheets of copper cathode being weighed and bundled for shipment.
 
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 Figure  6 - Blue colored, copper electrolyte solution produced from the SX  plant ready for electrowinning and copper cathode production.
 
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 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 Measured and Indicated Mineral Resource containing over 831.6  million tons with a total copper grade of 0.31% (Measured Mineral  Resource of 191.3 million tons at 0.37% and Indicated Mineral Resource  of 640.2 million tons at 0.29%), and a preliminary economic assessment  ("PEA") yielding robust economics including an NPV8% of $1.3  Billion, IRR of 20.9%, and payback period of 4.1 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 Strong and  Harris, South Star, and eight other deposits.
 
 For additional  information on the Gunnison Project, including the PEA and mineral  resource estimate, please refer to the Company's technical report  entitled "Gunnison Project NI 43-101 Technical Report Preliminary  Economic Assessment" dated effective November 1, 2024 and available on  SEDAR+ at  www.sedarplus.ca.
 
 Dr.  Stephen Twyerould, Fellow of AUSIMM, President and CEO of the Company  is a Qualified Person as defined by NI 43-101. Dr. Twyerould has  reviewed and is responsible for the technical information contained in  this news release.
 
 For more information on Gunnison, please visit our website at  www.GunnisonCopper.com.
 
 ABOUT NUTON
 
 Nuton  is an innovative venture that aims to help grow Rio Tinto's copper  business. At the core of Nuton is a portfolio of proprietary copper  leaching technologies and capability. Nuton has the potential to  economically unlock copper from hard-to-leach ores, including primary  sulfides and, in doing so, increase domestic production of critical  minerals to support the energy transition. Nuton technologies can  achieve market-leading recovery rates and boost copper production in  new, ongoing and historical operations, increasing resource utilization  and maximizing value.
 
 With significantly lower energy and water  needs than conventional concentrating and smelting, and the ability to  produce copper cathode at the mine site, Nuton offers a reliable source  of domestically produced copper, with a short mine-to-metal supply chain  and the ambition to set industry-leading ESG credentials.
 
 One of  the key differentiators of Nuton is the ambition to produce the world's  lightest environmental footprint copper while having at least one  Positive Impact at each of its deployment sites, across its five  pillars: water, energy, land, materials and society.
 
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 For further information regarding this press release, please contact:
 
 Gunnison Copper Corp.
 Concord Place, Suite 300, 2999 North 44th Street, Phoenix, AZ, 85018
 
 Melissa Mackie
 T: 647.533.4536
 E:  info@GunnisonCopper.com
 www.GunnisonCopper.com
 
 Cautionary Note Regarding Forward-Looking Information
 
 This  news release contains "forward-looking information" concerning  anticipated developments and events that may occur in the future.  Forward-looking information contained in this news release includes, but  is not limited to, statements with respect to: (i) the intention to  deploy the Nuton® technology at the Johnson Camp mine and future  production therefrom; (ii) the continued funding of the stage 2 work  program by Nuton; (iii) the details and expected results of the stage  two work program; (iv) timelines for future production and production  capacity from the Company's mineral projects; (v) expectations regarding  the timing and amount of 48C tax credits; (vi) the results of the  preliminary economic assessment on the Gunnison Project; and (vIi) the  exploration and development of the Company's mineral projects.
 
 In  certain cases, forward-looking information can be identified by the use  of words such as "plans", "expects" or "does not expect", "budget",  "scheduled", "estimates", "forecasts", "intends", "anticipates" or "does  not anticipate", or "believes", or variations of such words and phrases  or state that certain actions, events or results "may", "could",  "would", "might", "occur" or "be achieved" suggesting future outcomes,  or other expectations, beliefs, plans, objectives, assumptions,  intentions or statements about future events or performance.  Forward-looking information contained in this news release is based on  certain factors and assumptions regarding, among other things, Nuton  will continue to fund the stage 2 work program, the availability of  financing to continue as a going concern and implement the Company's  operational plans, the estimation of mineral resources, the realization  of resource and reserve estimates, , copper and other metal prices, the  timing and amount of future development expenditures, the estimation of  initial and sustaining capital requirements, the estimation of labour  and operating costs (including the price of acid), the availability of  labour, material and acid supply, receipt of and compliance with  necessary regulatory approvals and permits, the estimation of insurance  coverage, and assumptions with respect to currency fluctuations,  environmental risks, title disputes or claims, and other similar  matters. While the Company considers these assumptions to be reasonable  based on information currently available to it, they may prove to be  incorrect.
 
 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 future results, performance or  achievements expressed or implied by the forward-looking information.  Such factors include risks related to the Company not obtaining adequate  financing to continue operations, Nuton failing to continue to fund the  stage 2 work program, the breach of debt covenants, risks inherent in  the construction and operation of mineral deposits, including risks  relating to changes in project parameters as plans continue to be  redefined including the possibility that mining operations may not be  sustained at the Gunnison Copper Project, risks related to the delay in  approval of work plans, variations in mineral resources and reserves,  grade or recovery rates, risks relating to the ability to access  infrastructure, risks relating to changes in copper and other commodity  prices and the worldwide demand for and supply of copper and related  products, risks related to increased competition in the market for  copper and related products, risks related to current global financial  conditions, risks related to current global financial conditions on the  Company's business, uncertainties inherent in the estimation of mineral  resources, access and supply risks, risks related to the ability to  access acid supply on commercially reasonable terms, reliance on key  personnel, operational risks inherent in the conduct of mining  activities, including the risk of accidents, labour disputes, increases  in capital and operating costs and the risk of delays or increased costs  that might be encountered during the construction or mining process,  regulatory risks including the risk that permits may not be obtained in a  timely fashion or at all, financing, capitalization and liquidity  risks, risks related to disputes concerning property titles and  interests, environmental risks and the additional risks identified in  the "Risk Factors" section of the Company's reports and filings with  applicable Canadian securities regulators.
 
 Although the  Company has attempted to identify important factors that could cause  actual actions, events or results to differ materially from those  described in forward-looking information, there may be other factors  that cause actions, events or results not to be as anticipated,  estimated or intended. Accordingly, readers should not place undue  reliance on forward-looking information. The forward-looking information  is made as of the date of this news release. Except as required by  applicable securities laws, the Company does not undertake any  obligation to publicly update or revise any forward-looking information.
 
 
  SOURCE:  Gunnison Copper Corp. |