Non-executive director van Wyk has also been made executive director.
With the appointment of an MD, interim executive chairman Ian Daymond has reverted back to being non-executive chairman.
Olivier is a member of the Australasian Institute of Mining and Metallurgy and has experience in all aspects of coloured gemstone mining, marketing and sales.
He was most recently CEO of Richland Resources (LN:RLD), formerly TanzaniteOne, since March 2010 and has been a director of Bezant Resources (LN:BZT) since March 2007.
Van Wyk is an experienced operational team project manager who has worked in South Africa, Zambia, Namibia and Mozambique.
He previously managed Mustang's ruby and graphite activities through Regius Resources Group, which he co-founded and has a 60% interest in.
Mustang's former MD Christiaan Jordaan stood down from the company in November citing "personal reasons".