Copper Fox outlines model for Van Dyke

Executive Summary

• Copper Fox completed a preliminary geometallurgical model (PGM) for its 100 % owned Van Dyke in‑situ copper recovery (ISCR) project, identifying mineralogical domains and data gaps that must be addressed before advancing to a prefeasibility study (PFS).
• The PGM outlines recommended future metallurgical testwork—including whole‑core pressure leach tests, bottle roll testing, acid consumption studies, and detailed residue analysis—to reduce uncertainty in copper extraction and recovery.
• Completion of the PGM establishes sampling and testing protocols that will guide the next phase of work, supporting Copper Fox’s plan to move the Van Dyke project toward a PFS.

Key Details

• Project Context: The 2020 Preliminary Economic Assessment (PEA) projected annual production of 85 M lb of Grade‑A copper cathode at a $3.15/lb copper price, recommending advancement to a PFS.
• PGM Objectives: Identify mineralogical domains, pinpoint metallurgical data gaps across the deposit, and develop recommendations for future testing to support an updated geometallurgical model suitable for PFS level work.
• Mineralogical Domains Identified:
• Oxide zone – primary target for ISCR.
• Transition zone – significant for leaching behavior.
• Below transition/chalcocite zones – sporadic chalcopyrite and pyrite occurrences.
• Existing Metallurgical Testwork Gaps:
• Eight pressure‑leach tests (PRT) on whole core (2014).
• Sixty‑five bottle‑roll leach tests (BRT) (2023) from Phase I drill holes.
• Gaps in coverage could cause variability in copper extraction/recovery estimates.
• Future Testwork Recommendations:
• Conduct additional whole‑core PRT and BRT on representative samples from each mineralogical domain.
• Correlate BRT and PRT results, including residue assays to optimize acid consumption, leach cycle duration, and predicted copper extraction.
• Include solvent extraction of pregnant leach solutions in closed‑cycle PRTs.
• Perform detailed mineralogical studies on head samples and residues; quantify carbonates and clays.
• Sampling & Testing Protocols Established:
• Standardized sample preparation, subsampling for bottle‑roll testing, and defined column heights for pressure leaching.
• Evaluate higher initial acid content, sequential column tests, reverse‑flow pH optimization, and duplicate runs to refine leach kinetics.
• Conduct assay/mineral studies on leached residues.
• Qualified Person: Elmer B. Stewart, MSc, PGeol – President & CEO of Copper Fox – reviewed and approved all scientific and technical information per NI 43‑101.

Notable Quotes

“The PGM has identified the data gaps in the metallurgical coverage across the Van Dyke deposit and recommendations for future sampling to gain greater certainty on the metallurgical variability… The PGM is a critical part of the execution plan that maps out the scope, timing and estimated cost of the studies required to meet the threshold of a PFS level study.” – Elmer B. Stewart, President & CEO, Copper Fox Metals Inc.