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 10/10 is stronger than the peer average of 5.4/10.
Lifecycle Milestones
Construction Milestones
5 of 5 reached- Oct 2024 · Source
- May 2024 · Source
- Aug 2024 · Source
- Reached — date not disclosed · Source
- Reached — date not disclosed · 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.
Not in place: tailings facility.
Jurisdiction (40%)9/10
Arizona: Fraser PPI 2025 is 90.73 of 100 (rank 10 of 68), which maps to 9 on this site's scale. Arizona, United States — top-tier, low political-risk mining jurisdiction.
Infrastructure (40%)8.6/10
A confirmed mill, confirmed road access, confirmed grid power, and no confirmed tailings facility at Johnson Camp Mine and Gunnison Project, Cochise County, Arizona.
Nearby producing mine (20%)Not yet researched
No producing mine within 50 km in our reference list (nearest listed: Mission (ASARCO LLC), 93 km). That list doesn't cover every mining district yet, so a longer distance isn't scored as remote.
Acquisition Susceptibility
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 in the research, a producer that already owns part of the company, is scored from its disclosed strategic shareholders. A producer that is a joint-venture or earn-in partner on the project, rather than a shareholder, isn't captured yet.
How this score is built
- Disclosed pending dealSub-score: Not scored
No pending acquisition or merger disclosed (checked)
Not scored: having no deal in flight isn't held against a company.
Weight 26.25% - Producer's strategic stakeSub-score: Not scored
No producer holds a disclosed stake on file (holder register researched) See holders
Not scored: most juniors that do get bought had no prior toehold, so a missing stake says little either way.
Weight 25% - Distance to a producing mineSub-score:3.6/10
Nearest producing mine: Mission (ASARCO LLC), 93 km
10 next to a producing mine, 8 at 20 km, 5 at 50 km, 0 beyond 200 km.
Weight 22.5% · 46% here - Lifecycle stageSub-score:5.5/10
Stage: Production
Feasibility and permitting score 10, where deals cluster, and production 5.5; earlier stages score less, down to 1 at grassroots.
Weight 15% · 31% here - JurisdictionSub-score:9/10
United States: jurisdiction score 9/10
Our jurisdiction score, used as is: higher means lower political and permitting risk.
Weight 6.75% · 14% here - CommoditySub-score:8/10
Primary commodity: Copper
Gold 10, copper 8, silver 5, nickel and uranium 4, others 2: most majors' deals are for gold.
Weight 4.5% · 9% here
Weight is each input's share of the full score. “Here” is its share of this company's score: inputs that aren't scored are left out and the rest re-weighted, never counted as zero.
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, formerly Excelsior Mining, operates the Johnson Camp copper mine in Cochise County, Arizona, which began producing copper cathode in late August 2025 under a technology and funding partnership with Rio Tinto's Nuton venture. Its larger Gunnison copper project nearby has measured and indicated resources of 846.1 Mt at 0.33% Cu, containing 5,190 million lb of copper. The March 2026 updated preliminary economic assessment for Gunnison shows an after-tax NPV8% of US$1.96B and a 22.5% IRR at US$4.60/lb copper, with initial capital of US$1,556M and a 21-year mine life averaging 174 million lb of copper a year over the first 15 years.