Pinto Valley is Capstone’s long-life, multi-generational open pit copper mine. The mine provides unrivalled leverage to copper with growing production through quick payback, high impact projects. Concurrently, Capstone is evaluating Pinto Valley’s long-term growth potential beyond its current mine life.

An Exciting Future

>1 billion tonnes of M&I

Currently of Measured and Indicated Resources, not in Reserve

Current mine life to 2039

PV4 Expansion evaluating long-term growth potential of M&I Resource and expansion scenarios

Currently permitted to 79.5 ktpd

PV3 Optimization targeting 57 ktpd by 2021 and 60+ ktpd by 2022, with improved copper recoveries

Pinto Valley is currently the only operating mine located in the historic Globe-Miami mining district of Arizona, one of the oldest and most productive mining districts in the United States. Since its first recorded production in 1975, Pinto Valley has produced more than four billion pounds of copper, including 0.5 billion pounds of copper cathode. Capstone acquired Pinto Valley from BHP Billiton in October 2013 and is currently the second largest employer in the district and contributes over $270 million annually to Arizona’s economy.

Capstone is positioning Pinto Valley to be optimized in time for higher copper prices. PV3 Optimization focuses on innovation and a series of low-capital, quick payback projects to debottleneck operational performance, with the goal of higher throughput and higher recovery. 

A PV4 Study is evaluating the mine’s long-term growth potential of Measured and Indicated Resources (inclusive of Reserves) of over 1.36 billion tonnes at 0.30% copper. Scenarios include increased mining rates, higher mill grades and increased leaching. 

Innovation and Optimization 

Jetti Resources: Pinto Valley has successfully demonstrated positive economics by applying a novel patented catalytic technology from Jetti Resources to existing dump leach. The plan is to increase copper cathode production to 300-350 million pounds from mineralized waste over the next two decades, generating strong cash flow from the mine’s underutilized SX-EW plant, which is currently operating at only 20% capacity. Read the full news release or view the presentation.

Coarse particle flotation: Pilot plant testing of a new coarse particle flotation technology by Eriez Flotation Division, the world leader in innovative flotation technology, commenced in December 2020. Positive pilot plant testing showed that a 6 to 8% increase to overall copper recovery is achievable. Other benefits could be lower grinding costs, lower water and energy consumption and increased tailings stability via coarser tailings. The project is in final stage review, read the January 19, 2021 news release for more details. 

Time-Lapse of PV3 Optimization Work Completed in July 2020


Pinto Valley's Cultural Transformation


Pinto Valley Location

Geology and Mining

Geological setting Porphyry Copper Deposit - primary host rock is the Precambrian-age Lost Gulch Quartz Monzonite, (equivalent to the Oracle Granite or Ruin Granite).
Economic Mineralization Hypogene ore body with chalcopyrite, pyrite, and minor molybdenite as the significant primary sulfide minerals
Mining method Open pit
Primary product mined Copper
By-products mined Molybdenum

Technical Reports

Download item year list

Reserves & Resources

Pinto Valley Minerals Reserves, Remaining at December 31, 2019

Classification Tonnes (millions) % Cu % Mo Contained Cu (Mt) Contained Mo (Mt)
Proven 246 0.33 0.006 0.81 0.016
Probable 153 0.29 0.006 0.44 0.009
Total P+P 399 0.31 0.006 1.24 0.025

NOTE: Claydon Craig, P.Eng., Superintendent of Mine Technical Services at Pinto Valley is the Qualified Person responsible for the Pinto Valley Mineral Reserves estimate. Economic inputs to the block model were USD$2.75/lb Cu and USD$12.50/lb Mo. Mineral Reserves are reported above 0.175% Cu cut-off grade. Summation errors due to rounding. Contained metals are reported at 100%.

Pinto Valley Mineral Resources at 0.17% Cu Cutoff at December 31, 2019

Classification Tonnes (millions) % Cu % Mo Contained Cu (Mt) Contained Mo (Mt)
Measured (M) 567 0.33 0.006 1.89 0.034
Indicated (I) 791 0.28 0.005 2.24 0.040
Total M & I 1,357 0.30 0.005 4.13 0.074
Inferred 176 0.25 0.005 0.43 0.008

NOTE: Klaus Triebel, CPG., Chief Geologist at Pinto Valley, is the Qualified Person responsible for the Pinto Valley Mineral Resources estimate. Mineral Resources that were not converted to Mineral Reserves do not have demonstrated economic viability. Mineral Resources are presented inclusive of Mineral Reserves. Mineral Resources are reported as at December 31, 2019 above a 0.17% Cu cut-off grade. The economic assumptions for the reasonable prospects pit include: $3.30/lb Cu, $10.00/lb Mo, 88% Cu recovery, 50% Mo recovery, $1.50/ton mining costs, $1.50/ton G&A costs, $5.00/ton milling costs, and a pit slope of 45°. Totals may not tally due to rounding. Contained metals are reported at 100%.