"Peter's experience in running large and complex business across many different markets, as well as his considerable experience in the metals and mining industry, makes him ideal to take over the leadership of the business as it continues to grow rapidly across all our key pillars," Capital's executive chairman Jamie Boyton said.
With executive experience in resources and logistics spanning more than 25 years, Stokes' was most recently president for global logistics for leading logistics and transport business in Asia, Toll Group.
Prior to that, he was CEO of mechanized hard-rock underground mining company Barminco Limited.
He has also served as CEO of Linfox and as a partner at Accenture.
Advisory house Tamesis Partners said the "wealth of experience" Stokes brings will be important to Capital's growth.
Stokes, who will also join Capital's board as an executive director, will see his roles take effect from 3 October. He will be based in Perth, Australia.
Boyton will remain as executive chairman.
"With Jamie Boyton staying on in the executive chairman role, his decade plus of experience at Capital stays with the business as a significant asset for Mr Stokes to draw on," Tamesis said.
Capital's share price last closed at 82.20p (US$94.37). It had a market capitalisation of US$182 million.
Tamesis has a target price for Capital of 160p.