Gunnison Copper Corp (TSX:GCU, OTCQB:GCUMF) is shifting gears ahead of a catalyst-rich 2025 at its Arizona mineral properties.
The company, which up until late 2024 was known as Excelsior Mining, had long planned to extract copper at its Gunnison project using in-situ recovery but is now pivoting to open-pit mining, citing economic and operational advantages.
“The name change marks our transition,” CEO Stephen Twyerould told Proactive.
“Excelsior was focused on in-situ recovery, while Gunnison Copper is now moving forward with a large-scale open-pit mine.”
For investors, the shift could mean higher production volumes, improved cost efficiency, and a clearer path to commercialization. While in-situ recovery can face technical hurdles, an open-pit approach may de-risk the project and unlock new resource potential. With copper prices holding firm, Gunnison’s new strategy positions it to capitalize on a market hungry for the critical metal.
A strategic rebranding
The Gunnison deposit boasts over five billion pounds of measured and indicated copper.
An open-pit strategy offers several advantages, including enhanced infrastructure utilization across multiple satellite deposits and improved copper recovery rates. While in-situ methods targeted approximately 50% recovery from the oxide zone, the open-pit approach is projected to achieve closer to 70%, extending into the deeper sulfide zone.
"With strong copper prices and a bullish market outlook, the additional 20% recovery, combined with a longer mine life and higher production rates, made this transition an outstanding opportunity," Twyerould said.
Gunnison’s preliminary economic assessment (PEA), released in late 2024, outlines a significant open-pit operation with the capacity to produce approximately 167 million pounds of copper annually. With all-in sustaining costs estimated at $1.94 per pound and current copper prices hovering around $4.50, the projected margin of about $2 per pound positions Gunnison Copper favorably in the market. “At 170 million pounds annually, that adds up quickly,” Twyerould noted. “It’s a highly compelling project.”
Looking ahead, the next major milestone is the pre-feasibility study (PFS). The company has identified several opportunities to enhance the project's economics, which were not factored into the initial PEA. Over the next six months, Gunnison Copper will focus on a "high-value add" program, targeting key components that could significantly boost the project's value. By tackling these now, Gunnison can generate strong catalysts that will guide the PFS.
Exploring unique byproducts
Among the value-added components are unconventional byproducts: gravel and limestone, two byproducts that are not typical of most copper projects. As the open pit develops, the company anticipates mining through substantial gravel overburden and high-purity limestone. While traditionally considered waste, these materials may have significant value. "If even a portion of it can be sold, it directly benefits the bottom line because the mining cost is already accounted for," Twyerould explained.
Over the life of the mine, Gunnison can expect to extract more than 80 million tons of limestone. In the region, limestone sells for anywhere between $20 and $80 per ton, so if even a fraction of that is commercially viable, it provides another significant revenue stream.
Another quirk of the Gunnison deposit are high-grade copper veins distinguishable within waste material, which enables the potential use of optical sorting technology to separate copper-bearing material from waste, potentially reducing both operating and capital costs. Because Gunnison’s mineralization occurs in high-grade veins rather than disseminated oxide, the company can leverage optical sorting—a technology widely used in recycling and food processing— to scan and separate copper-bearing material from waste before processing.
Initial tests showed 100% accuracy in distinguishing copper-rich zones, suggesting significant potential to cut operating and capital costs by avoiding unnecessary processing of barren material. This efficiency could enhance project economics and extend mine life, Twyerould noted.
"If it proves viable, it could result in a materially positive change for the project," the CEO said.
Revitalizing the Johnson Camp Mine
In parallel, Gunnison Copper is advancing the Johnson Camp Mine (JCM), located just a few kilometers from the Gunnison Project. Partnering with Nuton LLC, a Rio Tinto venture, the company aims to apply advanced sulfide leaching technology to process existing sulfide material. Construction is underway, with copper production expected to begin later this year.
Twyerould calls Johnson a “small but meaningful” copper producer, utilizing Nuton’s cutting-edge sulfide leaching technology.
Beyond these projects, Gunnison Copper controls the entire Cochise mining district, encompassing numerous known deposits and historical mines. While the immediate focus remains on the Gunnison Project and JCM, the broader exploration potential offers substantial upside. "We believe there's significant value to be unlocked," Twyerould said.
Gunnison’s strategic shift to open-pit mining, combined with innovative approaches to resource utilization and a focus on enhancing project economics, positions it well within a robust copper market.
“Right now, our primary focus is on the Gunnison project because of its significant value, and we are also bringing Johnson Camp into production,” the CEO said.
“Beyond that, we control a whole mining camp with geophysical anomalies and deposits that haven’t had modern exploration since the 1970s. We believe there’s substantial upside.”