Gunnison Copper Achieves Commercial Production at Johnson Camp Mine

Gunnison Copper Corp. (GCU) announced that its Johnson Camp Mine (JCM) in Cochise County, Arizona, achieved commercial production in September 2026. This declaration follows record monthly output in August and continued production "above the required operating threshold" through the first half of September. The company restated its nameplate capacity at "up to 25 million pounds of copper cathode per year, which the Company is ramping up to."

GCU reported that August 2026 copper cathode production reached 1,304,448 lbs, described as the highest monthly production since operations restarted. From September 1–17, 2026, copper cathode production totaled 894,767 lbs. The company claims the facility produces 99.999% pure copper cathode on site from Arizona ore, with no offshore smelting or refining. Earlier releases in the same news history cited 99.99% purity; the additional decimal point represents a promotional inconsistency rather than new technical data.

The JCM asset is restated as "fully funded by Nuton LLC, a Rio Tinto Venture." While previous filings, including the Q2 2026 release on August 13, 2026, and the Q2 MD&A, stated that nameplate capacity was "targeted by year-end 2026," the current release does not attach a date to achieving this capacity. The definition of the "required operating threshold" used to declare commercial production is not quantified or disclosed. Additionally, the release contains no discussion of the September 16, 2026 decision to abandon the Department of Energy 48C tax credits.

Gunnison Copper Corp. (GCU) delivered commercial production at its Johnson Camp mine within the window guided for the third quarter of 2026, as outlined in the company’s August 13, 2026 release and Q2 2026 MD&A outlook. The announcement covers production tonnages for August 2026 and the period from September 1 to 17, 2026. The release does not include cost data, such as cash cost or AISC, nor does it provide grade, recovery, revenue, unit margin, or reserve figures. It also does not alter any inputs for the Preliminary Economic Assessment (PEA) or Pre-Feasibility Study (PFS).

All figures reported are mine-level for Johnson Camp and period-specific. They should not be compared with company-wide revenue or the Gunnison Project PEA’s $2.05/lb AISC, as these represent different assets on different timelines. The release does not restate that Johnson Camp Mine (JCM) copper revenue accrues to Nuton until Nuton recovers its financing of the project, a detail disclosed in the September 25, 2025 first-sale release. Prior-period context from Q2 2026 shows revenue of US$23.6 million, split into US$13.7 million of copper cathode sales and US$9.8 million of "deferred mining and processing demonstration service revenue." Consequently, commercial production serves primarily as an accounting and de-risking event involving revenue recognition, capitalization of ramp-up costs versus depreciation, and the unwinding of the Nuton obligation, rather than a free-cash-flow event for Gunnison shareholders.

Market data shows the stock trading at C$0.43 on September 18 and C$0.46 on September 21, up from C$0.33 on July 23, representing a approximately 39% recovery leading into this milestone. The release has not yet traded. The event is considered positive but expected, as it does not change the net asset value, cash flow to Gunnison, cost structure, or timeline beyond what was previously communicated.

Gunnison Copper Corp. (TSX: GCU, OTCQB: GCUMF, FSE: 3XS0) is a multi-asset, pure-play copper producer and developer that controls the Cochise Mining District in the Southern Arizona Copper Belt, an area described as containing 12 known deposits within an 8 km economic radius.

The company’s producing asset, the Johnson Camp Mine, features a 25 Mlb/yr nameplate SX/EW capacity. Production is fully funded by Nuton LLC, a Rio Tinto venture, and is scheduled to begin processing run-of-mine oxide from August 2025 and Nuton bioleach sulfide material from December 2025. Rio Tinto's Nuton technology targets approximately 30,000 tonnes of refined copper over a four-year demonstration period, with recovery rates up to 85% and a claimed carbon intensity of 0.82 kg CO2e/kg Cu.

The Gunnison Project, a development asset, holds 846.1 Mt of measured and indicated resources grading 0.33% total copper, equating to 5.19 billion pounds. The open-pit, heap-leach, SX/EW operation includes a direct rail link. A preliminary economic assessment (PEA) dated March 2026 projects a life-of-mine gross revenue of US$14.5 billion and unlevered free cash flow of US$9.9 billion. The project demonstrates a 21-year life with production of approximately 174 Mlb/yr for years 1–15, yielding an NPV8% of approximately US$2.0 billion (US$1,959 million), an IRR of 22.5%, and a payback period of 3.9 years. The profitability ratio, defined as NPV8% divided by initial capex, stands at 1.3. Price sensitivity analysis indicates the NPV8% ranges from US$1.6 billion at $4.25/lb to US$4.6 billion at $7.00/lb.

The mine plan also includes the Strong & Harris satellite, which contains inferred resources of 76 Mt at 0.49% total copper, plus zinc and silver credits. This deposit is within trucking distance of planned infrastructure. South Star, a copper-zinc-silver deposit, is described as the next most advanced satellite, followed by eight other deposits.

Management includes Craig Hallworth as President and CEO, having been promoted from CFO effective May 15, 2026, succeeding retiring founder Dr. Stephen Twyerould, who remains on the board. Other executives include Bjorn Meyer, COO; Matt Bingham, SVP Permitting and External Affairs; Roland Goodgame, PhD, SVP Business Development and the Qualified Person on this release; Fabio Rocha, interim CFO since May 15, 2026; and Melissa Mackie, VP IR. Michael "Brian Penney" was nominated to the board at the June 25, 2026 AGM.

A governance note indicates that the investor presentation still names Stephen Twyerould as Qualified Person, despite his retirement as CEO in May 2026 and the current release naming Dr. Roland Goodgame. Part of the presentation appears stale. Separately, the CFO seat has been held on an interim basis since May 2026.