Option Announced To Joint Venture On The Cactus Project

CASA GRANDE, AZ - Arizona Sonoran Copper Company Inc. has entered into an option to joint venture agreement with Nuton LLC, a wholly-owned subsidiary of Rio Tinto, to establish a strategic alliance for deployment of the Nuton technologies at its Cactus Mine and the Parks/Salyer Project, in Arizona.

George Ogilvie, President and CEO, said, “We are delighted to announce this strategic joint venture transaction with Nuton. We welcome the expertise and financial support as we expand testing of Nuton’s heap leaching technologies, while concurrently advancing ASCU’s projects. Nuton’s column test results have demonstrated continued improvements in extraction rates from both the primary and enriched mineral resources, resulting in potentially more efficient operations. We look forward to advancing into Phase 2 testing, which includes an expanded understanding of the Nuton technologies’ economic benefits within a fully-integrated pre-feasibility study, anticipated by the end of 2024.

The company also reported metallurgical results from the Nuton Phase 1 column leach program from Cactus copper porphyry project.

Ogilvie said, “We are encouraged by the extraction rates resulting from our primary and secondary sulphides using the Nuton™ technologies. These results demonstrate a continued extraction rate improvement from the columns reported in June. Nuton’s heap leaching technology is a potential solution to gain access to our currently stranded primary mineral resource while also incrementally improving the copper extraction rates from the enriched material. Particularly interesting to ASCU, is that Nuton’s flow sheet could be integrated into the planned Cactus heap leach and SXEW flow sheet. With a successfully negotiated Commercial Framework Agreement in place and a completed Phase 1 test program, we would seek to coordinate the improved extraction rates into an updated and expanded technical study, complementing the base case PFS anticipated in Q1 2024 and demonstrating economies of scale.”

On the Cactus deposit, a total of 23 small column leach tests (3 ft | 1 m) on 10 ore types, plus a Life of Asset (LoA) Blend, are currently completed or in progress. Preliminary test work results indicate that using Nuton additives at elevated temperatures have the potential to significantly enhance chalcopyrite extraction in the LoA blend and the other primary sulphide ore types. The highest copper extraction achieved to date for the LoA Blend is 80%. Condition optimizations, including a higher temperature control for the LoA blend is currently underway, with the target of consistently exceeding 80% extraction rates. Acid consumption for the primary sulfide ores ranges from 10 to 60 kg/t. For the higher acid consuming ores, increasing the pH appears to have a positive effect on acid consumption, but also a negative impact on the rate of copper extraction. Nuton will continue to analyze residue samples that may yield further insights. Copper extractions from the secondary sulfide dominant ore types at elevated temperatures are very high, ranging from 86% to 98%. These ores contain very little reactive gangue, consequently most of the ore types are net acid generators.