Gunnison Copper Corp.
Gunnison Copper (formerly Excelsior Mining) operates the in-situ-recovery Johnson Camp Mine in Cochise County, Arizona -- producing copper cathode under a technology and offtake partnership with Rio Tinto's Nuton LLC since first commercial sales in September 2025 -- and is separately advancing a March 2026 PEA on its larger Gunnison in-situ copper project outlining a US$2.0 billion after-tax NPV8% and 23% IRR.
Notable vs. Peers
- Financials score of 9.1/10 is stronger than the peer average of 5.3/10.
Lifecycle Milestones
Construction Milestones
5 of 5 reached- Oct 2024 · Excelsior Mining (now Gunnison Copper) received the final permits required to restart Johnson Camp Mine: amended Mined Land Reclamation Plan, Air Quality Permit and Aquifer Protection Permit -- all approvals needed to start copper production. [Task #697 chronology ruling, 2026-08-25] NOT A DATE ERROR. Task #696's permit rule flags this row as postdating CONSTRUCTION_START (2024-08-08). Both dates are correct and the sequence is real: Johnson Camp is a previously-permitted, previously-operating mine, so the August 2024 construction work (new leach pad, overliner crushing) proceeded under authorisations already in hand, and what this row records -- an amended Mined Land Reclamation Plan, Air Quality Permit and Aquifer Protection Permit -- is the FINAL permit package needed "to start copper production", per the cited release's own framing. The permit authorised production, not the construction that preceded it. Staged permitting across a restart, one slot in the chain: the same shape as ARTG/Blackwater and distinct from the multi-asset (SBMI) case. Flagged for a reviewed exception (key: PERMIT_GRANTED_AFTER_CONSTRUCTION_START); the ticker's other inversion, PERMIT_GRANTED_AFTER_CONSTRUCTION_DECISION, is already covered by the rule's conditional-FID expectedGap. Not added to the rules file here because it was under concurrent edit. · Source
- May 2024 · Nuton LLC (a Rio Tinto venture) elected to proceed to Stage 2 of its Option Agreement with Excelsior Mining, funding construction at Johnson Camp under its Nuton copper heap-leach technology. · Source
- Aug 2024 · Excelsior Mining announced construction had commenced at Johnson Camp Mine (new leach pad, overliner crushing), with first copper production anticipated H1 2025; M3 Engineering awarded the EPCM contract. · Source
- Reached — date not disclosed · First production of pure copper cathode from the fully operational Johnson Camp Mine occurred in the last week of August 2025 (SX/EW circuit start-up announced Aug 11, 2025; official 'first copper production' announcement Sept 3, 2025). Exact day not confirmed from available sourcing -- recorded reached-but-undated. · Source
- Reached — date not disclosed · Genuinely reached, but no source found uses formal 'commercial production declared' language: first copper cathode production at the Johnson Camp Mine (Arizona) commenced the last week of August 2025, with inaugural copper sales completed 2025-09-15 ('beginning of commercial revenue generation') -- genuinely reached and sustained for a year, ramping toward the plant's 25 million lb/year design capacity by mid-2026. Johnson Camp is Gunnison's sole current producing asset (funded/supported by Nuton LLC, a Rio Tinto venture, but Gunnison itself owns and operates the mine). Left null with the August/September 2025 context noted. This row was missing entirely prior to 2026-08-21 -- a genuine data gap, not a stage error; Miner.stage was already correctly PRODUCTION. · Source
Milestones are recorded only from a company's own dated disclosure. A milestone with no date shown is one we can confirm was reached but for which no date was disclosed — we don't estimate one. "Not yet reached" means exactly that, not that a date is missing. An "Expected" line likewise only ever reflects the company's own guidance (e.g. a study or permit decision targeted for a stated quarter) — most not-yet-reached milestones have none, and that absence means no such guidance has been disclosed, not that one is overdue.
A relative ranking of how closely this company matches the profile of juniors that have actually been acquired — not a probability, and not a reason to buy. Acquisitions are rare: only a few dozen significant deals happen a year across a universe of thousands of juniors, so even a high score here describes a long shot. The strongest signal the underlying research identifies — whether a major already holds a JV, earn-in, or 5–19.9% strategic stake — isn't tracked yet and is absent from this score.
Your Rankings
Management Team
President and Chief Executive Officer of Gunnison Copper Corp., promoted effective May 15, 2026, succeeding Dr. Stephen Twyerould, who remains on the Board as part of a planned retirement transition. Previously served as Senior Vice President and Chief Financial Officer of the company, where he led the strengthening of its balance sheet, including the elimination of secured debt, a significant expansion of its institutional shareholder base, and improved economics of the Gunnison Copper Project.
Interim Chief Financial Officer of Gunnison Copper Corp., appointed effective May 15, 2026 as part of the leadership changes accompanying Craig Hallworth's promotion to CEO. Previously served as the company's Director, Accounting & Reporting, with experience in financial leadership roles within the mining sector.
Chief Operating Officer of Gunnison Copper Corp., appointed effective June 26, 2026, succeeding Robert Winton. Brings more than 20 years of Arizona mining experience spanning operational leadership, mine development, engineering and project execution across large-scale copper operations. Most recently President of Cripple Creek & Victor Mining Company (an SSR Mining operation); previously Vice President of Operations and Executive Director of Innovation and Growth at Panasonic Energy Corporation North America, and spent 20 years at ASARCO including over a decade as General Mine Manager of the Mission Complex.
Senior Vice President, Permitting & External Affairs of Gunnison Copper Corp., appointed as part of the May 2026 leadership strengthening. Mining and environmental attorney with U.S. permitting expertise; previously held senior roles at Hudbay Minerals managing legal and permitting matters for the Copper World project.
General Counsel and Corporate Secretary of Gunnison Copper Corp. (Corporate Secretary role effective June 1, 2026). Corporate and securities lawyer with over 20 years advising public companies; began his career at Blake, Cassels & Graydon LLP.
Vice President, Investor Relations & Communications of Gunnison Copper Corp., promoted as part of the May 2026 leadership strengthening. Has led the company's investor relations and communications strategy since July 2025, with over 10 years of capital markets and investor communications experience in mining.
Chief Metallurgist of Gunnison Copper Corp. Seasoned metallurgist with copper processing expertise; previously held roles at Rio Tinto and Freeport-McMoRan.
Chief Geologist of Gunnison Copper Corp. Exploration and resource geologist specializing in copper systems; previously with Agnico Eagle Mines, Goldcorp and Silver Standard Resources.
Vice President, People of Gunnison Copper Corp., promoted as part of the June 2026 leadership changes accompanying Bjorn Meyer's appointment as COO. Accomplished human resources executive with extensive experience in Arizona mining.
Insiders, Investors & Smart Money
Notable shareholders and insiders whose involvement is worth knowing about, plus what we're seeing from institutional/large-investor activity.
Gunnison's backer is Nuton LLC, a Rio Tinto venture, which is funding roughly US$167M into the Johnson Camp Mine on a non-dilutive basis and holds an option to take 49% of that asset once commercial production is established. Nuton has funded the work programme since the January 2023 collaboration agreement, advanced it to Stage 2 in May 2024, added US$3M in March 2025, and first produced copper cathode through its own circuit in December 2025 -- but it owns no shares in Gunnison itself. Greenstone Resources II LP, the mining private-equity fund that backed the company for a decade, sold its entire 33.88% holding in February 2026 as the fund reached the end of its life, leaving no specialist investor on the register.
No notable insiders tracked for this miner yet.
Reports, Presentations & Documents
Gunnison Copper Project PEA (updated), NI 43-101 technical report effective 18 Mar 2026, filed 31 Mar 2026: post-tax NPV(8%) ~US$1.96B, post-tax IRR 22.5%, 3.9-year payback, 21-year mine life, initial capital US$1,556M, base case copper price $4.60/lb, average annual production 174M lb Cu (first 15 years), LOM recovered copper 3.187B lb, AISC $2.05/lb. Measured+Indicated mineral resource 846.1 Mt @ 0.33% Cu (5,190M lb contained Cu) -- PEA-stage only, includes Inferred material in the mine plan, no mineral reserves declared. IMPORTANT: this PEA covers Gunnison Copper Corp's flagship growth project (open-pit/heap-leach/SX-EW, not yet built) -- it is NOT the same asset as the company's currently-producing Johnson Camp Mine, which reached first production Aug 2025 under a Nuton LLC (Rio Tinto venture) funding/technology partnership (up to 25M lb/yr finished cathode capacity, ~$100M+ funded by Nuton with no exposure to Gunnison until Nuton recovers its investment). No separate NPV/IRR/mine-life study was found for Johnson Camp itself in this pass (Nuton-funded restart operating off a sulfide-leaching PEA from 2023, not re-verified here). ouncesFound left null -- see repo-wide OPEN POLICY QUESTION on the ouncesFound/copper unit mismatch (docs/GOLD-DATA-OPERATIONS-PLAYBOOK.md Section 9 Step 0 / Task #324), not resolved unilaterally here.