They will replace directors Matt Idiens and Dave Pelham, who plan to retire after the company's annual general meeting later this year.
Both directors will also join the company's technical advisory committee, of which Roux has been made chairman.
He was most recently COO of Endeavour mining and has over 42 years' experience in the mining industry, with previous experience at Anglo American, De Beers and AngloGold Ashanti.
Nutter was a mining analyst at Capital Group from 2004 until he retired in 2017. Prior to this he spent 13 years at RBC Capital Markets where he was managing director after being the bank's director of global mining research and chairman of the strategic planning committee.