The US Geological Survey estimates that the undertaking hosts million 68.7 million tonnes of ore at a grade of 0.66% copper. Manufacturing totalled 895 lb. of copper, together with 75 million lb. of copper cathode.
The Pinto Valley open pit mine, concentrator and solvent extraction/electrowinning (SX/EW) plant are situated about 125 km east of Phoenix. Manufacturing started in 1975, and since that point the mine has produced greater than 4 billion lb. of copper, together with 500 million lb. of copper cathode. Capstone acquired the undertaking from BHP Copper in 2013.
“We imagine Copper Cities is geologically a mirror picture of Pinto Valley with the identical host rocks and age,” stated Capstone senior VP of strategic undertaking and exploration Brad Mercer. ”Our plan at the moment underway requires a C$6.7 million two part drill program aimed toward twinning historic drill holes and to pick out a portion of those for metallurgical testing.”
Capstone is at the moment learning how Pinto Valley manufacturing might be elevated to extend cathode manufacturing to 300 million to 350 million lb. yearly from mineralized waste over the twenty years. Known as PV4, the examine contains the potential use of three technological improvements:
- Jetti catalytic leach technology, which might enhance cut-off grades to the mill and enhance leachable tonnage by upping mining charges, elevating mill grades and growing leaching. A column leach check is being carried out within the first half of this 12 months.
- Coarse particle flotation know-how, which might enhance copper restoration by at the least 6% to a complete of about 90% whereas offering the flexibleness to spice up mill throughput.
- Pyrite agglomeration, which might divert acid-generating minerals reminiscent of chalcopyrite from tailings to the dump leaching operation so extra copper might be recovered and among the acid mandatory for manufacturing could possibly be generated. The capital value of agglomeration could be about C$7 million ($5.6m) with a one-year payback.
Final June, Capstone accomplished its SV3 mill optimization undertaking, which included changing the shell of ball mill #3. The undertaking elevated throughput and copper restoration whereas lowering water consumption by upgrading the tailings thickeners.
The Pinto Valley undertaking has measured and indicated assets of 1.4 billion tonnes grading 0.29% copper (8.9 billion contained lb.) and 0.006% molybdenum (170 million contained kilos). The inferred useful resource is 170.6 million tonnes at 0.26% copper and 0.006% molybdenum.
Except for Pinto Valley, Capstone operates the Cozamin copper-silver-mine in Mexico and is growing the Santo Domingo copper-iron-gold undertaking in Chile. The corporate met its 2021 manufacturing tips with 85,000 tonnes of copper from Pinto Valley and Cozamin.
This 12 months tips have been set at 82,000 tonnes to 90,000 tonnes of copper together with that offered by the Santo Domingo undertaking. Capstone additional stated it plans to spend $153 million on capital initiatives and $11.2 million on exploration in 2022.
(This text first appeared within the Canadian Mining Journal)