Copper 360 Limited yesterday announced a significant development at its Rietberg Copper Mine with the declaration of its maiden Reserve and the concomitant filing of a comprehensive Mining Viability Study (MVS).
The declared Mineral Reserves at Rietberg stand at an impressive 2.48 million tonnes (Mt) with a copper grade of 1.38%. This declaration comes after meticulous modelling and survey verification, which also identified existing broken ore in various underground draw points.
Last September, the company announced a resource upgrade that saw the total resource of contained copper increase by 220% from 25,275 tonnes in 2022 to 81,200 tonnes, with the maiden and indicated resource of 60,800 tonnes of copper declared at the time.
The Mineral Reserve now includes a Crown Pillar section which adds to the resource base with an estimated Proven Reserve of 94,000 tonnes at 1.17% copper. Over the mine’s lifespan, the all-in-sustaining unit cost (AISC) for copper contained in concentrate is estimated at R81,903 per tonne (equivalent to US$4,427 per tonne).
Additionally, the Probable Reserve estimate now includes 500,000 tonnes of “fringe-ore” left behind along the sidewalls of the stope from previous mining, with a grade of 1.37% copper.
As a result of these developments, the Rietberg Mine’s Reserves have increased by approximately 50% of the previously declared Mineral Resource (Measured and Indicated). As the engineers’ confidence continues to improve, further conversion of inferred resources is anticipated.
A detailed Mining Viability Study was recently published, merging technical and commercial evaluations to gauge the viability of the company’s Long-Term Operational Plan (LoM). This plan outlines the development of essential infrastructure and forecasts the production capacity that will support future mining endeavours. The Life of Mine Plan (LOMP) has incorporated approximately 50% of the previously declared Measured and Indicated Resource, focusing on “high grading” the Rietberg orebody while minimising dilution.
However, some resources are classified as Rock Mechanic Exclusion Zones, which prohibit mining on the western side of the underground void due to the presence of an inverted sidewall just below the crest. This exclusion results in an ore loss of approximately 1.3 million tonnes from the potential mineable reserve, leaving 2.48 million tonnes (including void tonnage) as the final mineable reserve. The Run of Mine (ROM) tonnes comprise 72% of the total mineable ore reserve. The required engineering to extract this portion of the ore is still in its conceptual design stage and is expected to be completed as part of an independent study.
The declaration followed confirmation earlier this week that the company has restarted mining activities at Rietberg Mine after a forty one year pause in copper-related mining in the Northern Cape.
Copper 360 chief executive Jan Nelson said that the mine study and reserve declaration marks a significant milestone in Copper 360’s capacity. “After commencing mining activities recently, now supported by the Reserve Declaration and report, It again underscores our commitment to mining in the Northern Cape,” he said. “The updated Reserve and Resource statement better represents our findings and positions the company for a bright future as a copper producer,” Nelson added and noted that the study further indicated Copper 360’s dedication to responsible resource utilisation and sustainable mining practices.”
“Copper 360 is relentless in its approach to advancing its extraction strategies and enhancing the value of its operations,” Nelson said. “We will achieve this through rigorous engineering and continuous improvement.”
The Ore Reserves and Mineral Resources, upon which the mining plan and production targets are modelled, have been expertly prepared by qualified professionals in strict compliance with the Alt-X JSE listing rules.
