United Manganese of Kalahari (UMK) is a South African company, mining manganese in the John Taolo Gaetsewe District Municipality in the Northern Cape Province of South Africa. The Kalahari manganese fields are regarded as the largest manganese ore deposit globally. Established in 2005, UMK is 51% black owned and is the 4th largest manganese exporter in South Africa. In 2018 the mineral resources were estimated at 607mt with 200mt in measured and indicated categories. Mineral Reserves for Open Pit Mining are estimated at 112mt that provides a life of Open Pit Mine of more than 30 years.