The company, which bought Pinto Valley last year, says average annual production for the first five years is targeted at 128.4 million pounds of copper in concentrate and 6.6 million pounds of copper cathode.
Annual production for the life of the mine is 119.5 million pounds of copper in concentrate plus 6.3 million pounds of cathode copper.
The after-tax value, discounted at eight per cent, is US$738 million while capital costs are estimated to be $187.9 million over roughly 12 years.
In April 2013, Capstone Mining announced it would buy the Pinto Valley mine and the associated San Manuel Arizona Railroad Co. in Arizona from a subsidiary of BHP Billiton for US$650 million.
The life of the mine, located in Arizona's Globe-Miami mining district, about 125 kilometres east of Phoenix, was initially expected to stretch until 2018.
"Completion of the (pre-feasibility study) ... provides us with the platform to stabilize operations, gain efficiencies and gives us the opportunity to take a longer-term view towards the future of the Pinto Valley mine," said president and CEO Darren Pylot.
"As well as pursuing operating efficiencies, we have started the work required to evaluate a possible mine life extension beyond 2026 and a potential increase in throughput."