Arizona Sonoran Copper Company Inc., an emerging US-based copper developer and near-term producer, announces the first set of drilling results from its 8 initial diamond drill holes for over 2,938 m (9,639 ft) along the western periphery of the Cactus West pit. The drilling demonstrates continuous leachable mineralization including extensions outwards from the modelled pit shell by at least 61 m (200 ft). Mineralization from the infill drilling remains open to the west (see FIGURES 1 – 3) and TABLE 1 below.
Deposit Model of a Porphyry Copper Deposit (Modified from Lowell and Guilbert, 1970). Image Credit: Arizona Sonoran Copper Company Inc
The 2021 mineral resource conversion drill program was designed to upgrade the current mineral resources at the Cactus West Open Pit and Cactus East Underground, from inferred to indicated and from indicated to measured resources in advance of current ongoing technical studies. Additionally, the program informs mineral resource growth zones for the 2022 expansion drilling program set to begin shortly. A full set of drill highlights may be found in TABLE 1, below.
Drilling Highlights (please see TABLE 1 for full set of drilling results)
- Leachable material identified extending 61 m (200 ft) west from the modelled open pit
- ECW-029 0.774 % Cu TSol over 34 m (113 ft) of enriched mineralization
- ECW-025 0.272% Cu TSol over 108 m (355 ft) of oxide mineralization
- ECW-022 0.519% Cu TSol over 40 m (130 ft) of enriched mineralization
- ECW-023 0.695% Cu TSol over 15.3 m (50.3 ft) of enriched mineralization
George Ogilvie, Arizona Sonoran President and CEO stated, “These drilling results are the first of many exciting developments at the Cactus Project. The drill program is designed to target some materials previously viewed as waste by ASARCO, who at that time were processing sulphide-only material through a floatation mill. With ASCU targeting the leachable materials which sit atop the sulphide mineralization for a heap leach operation, the infill to indicated and measured drilling program may positively affect the starter resource base and ultimately the economics of the pit.
He continued, “The first priority at Cactus is mineral resource conversion as we gear up for the upcoming Prefeasibility Study in 2022 with maiden reserves. Shortly, however we will look to Park/ Salyer for pure exploration drilling in conjunction with Cactus Drilling.”
Geological Description
The Cactus West Orebody extends southwesterly at depth under the western highwall of the pit and beneath the bounding West Fault. Oxide and upper enriched ore zones were intersected to the west of the pit wall in 2020 step out drilling and were further targeted by the current infill program. This portion of the drilling traces the NE-SW trend of the high-grade center of the historic Sacaton West orebody. Results from this portion of the current drilling reinforce the positive results from the previous step out drilling in this area. Core drilling continues northward up the western edge of the pit to complete this successful phase of infill drilling. Condemnation hole, ECW-027, was drilled as a sterilization hole to define the ultimate edge of the western pit for infrastructure planning purposes, located 305 m (1,000 ft) west of the open pit.
Quality Assurance / Quality Control
Drilling completed on the project in 2020 was supervised by on-site ASCU personnel who prepared core samples for assay and implemented a full QA/QC program using blanks, standards and duplicates to monitor analytical accuracy and precision. The samples were sealed on site and shipped to Skyline Laboratories in Tucson AZ for analysis. Skyline’s quality control system complies with global certifications for Quality ISO9001:2008.
Technical aspects of this news release have been reviewed and verified by Allan Schappert – CPG, who is a qualified person as defined by National Instrument 43-101– Standards of Disclosure for Mineral Projects.