Arizona Sonoran (TSX: ASCU, OTCQX: ASCUF) has issued an updated mineral resource estimate for the Cactus brownfield copper project in Arizona to include the seven-month drilling program recently completed on the new MainSpring property.
Total measured and indicated resources came to 632.6 million tonnes at 0.58% total copper for 7.3 billion lb. of copper, while inferred resources are 474 million tonnes at 0.41% total copper for 3.8 billion lb. of copper.
The infill drilling at Parks/Salyer contributed to a 26% increase in the M+I resource and a 60% increase in inferred resource over the previous estimate, including the conversion of 1.2 billion lb. of copper into the measured category.
Another key change is the confirmation of the Parks/Salyer resource area and MainSpring as one single deposit, containing about two-thirds of the total mineral resource (4.8 billion lb. M+I, 2.6 billion lb. inferred) at Cactus.
The expanded Parks/Salyer deposit is amenable as an open pit that will be incorporated into a new preliminary economic assessment (PEA), which the company aims to complete this summer.
Also comprising the project are the Cactus West and Cactus East deposits as well as the Stockpile area, all located along a 5.5 km trend. No material changes are reported for these resource areas since the last update.
According to Doug Bowden, Arizona Sonoran’s VP exploration, these mineral resource areas have responded “favorably and impressively” to infill drilling with a consistently high conversion rate into higher classifications.
“The new Parks/Salyer deposit, inclusive of MainSpring could be transformational for the company as we foresee the opportunity to right size a larger operation and rescope Parks/Salyer to an open pit mine,” George Ogilvie, Arizona Sonoran CEO, stated.
“The pending result would lead to reduced mining execution risks and lowered operating costs which could manifest themselves in improved project economics.” Compared to the project’s first resource established in 2021, the new estimate represents growths of 353% and 94% on the M+I and inferred categories, respectively, in terms of contained copper content.
Earlier this year, the company already completed a prefeasibility study for the Cactus project, outlining a 21-year copper operation producing 110 million lb. of payable metal annually. Post-tax net present value (at 8% discount) is estimated at US$515 million, with an internal rate of return of 15.3%.
Subjective a positive PEA and, subsequently, a new PFS, Arizona Sonoran plans to complete a definitive feasibility study for the copper mine project by the end of 2025.
