Dual-listed Arizona Sonoran Copper Company has mutually agreed with Nuton, a venture of Rio Tinto, to terminate the option to joint venture (OTJV) on the Cactus project, with immediate effect.

The termination also includes the conclusion of Nuton’s investor rights agreement with the company.

President and CEO George Ogilvie said the companies had worked constructively to evaluate the potential application of Nuton’s technology at Cactus in Arizona, US.

“We appreciate Rio Tinto’s endorsement of the Cactus project through Nuton’s initial investment and shareholding, together with the constructive joint work under the OTJV to study the potential of deploying Nuton technology at the Cactus project. It has been a productive relationship, and we look forward to continuing engagement and dialogue with a valued shareholder in Nuton-Rio Tinto.

He said Arizona Sonoran would now continue advancing the Cactus brownfields project on a standalone basis, with a feasibility study and final permit amendments expected later this year. A final investment decision is contemplated as early as the fourth quarter of 2026.

"Over and above the pending feasibility study mine plan which will outline the extraction of oxides and enriched materials, there remains significant upside at the Cactus project with opportunities to potentially develop the significant primary sulphide mineral resource at depth, as disclosed in the prefeasibility study technical report, and in planned further exploration of the ‘Gap Zone’ and the ‘NE Extension’.”

Under the terms of the termination, Arizona Sonoran will make total potential payments of up to $34.96-million to Nuton, structured in three components. An immediate payment of $15-million is due on signing, followed by a deferred payment of $5-million payable on the earlier of the one-year anniversary of the termination agreement or the consummation of a change-of-control transaction.

A further contingent deferred payment of $14 957 816 will be payable only on the consummation of a change-of-control transaction that is publicly announced or subject to a definitive agreement within 24 months of signing the termination agreement.

The companies said the termination was completed largely in line with the applicable terms of the OTJV.

In connection with the termination, Nuton has agreed to provide Arizona Sonoran with all non-interpretative results from completed analyses of Cactus ore samples, as well as any completed Phase 2 metallurgical testing conducted by or on behalf of Nuton under the OTJV prior to its termination.