Mpumi was appointed CEO of Kumba Iron Ore in January 2022. Mpumi started her career at De Beers in 2001 as a Process Engineer and held various leadership roles within production management, projects and sales including General Manager of the Voorspoed diamond mine in South Africa. Mpumi was appointed Deputy CEO of De Beers Consolidated Mines in November 2017, and Managing Director, De Beers Group Managed Operations, in April 2019.