Petra Diamonds Ltd. said Dec. 9 that it is stopping operations at its Cullinan, Finsch, and Koffiefontein mines in South Africa due to a power system emergency declared by electricity public utility Eskom, and an unprecedented stage 6 load shedding after a technical fault at the Medupi Power Station.

Load shedding is a controlled measure to ensure that the national power grid remains stable to avoid a total countrywide blackout, according to Eskom. Stage 6 load shedding means 6,000 MW will be shed.

Petra said production, hoisting and processing at the mines have stopped with immediate effect. The company is now removing all people from underground, except those required for essential services, with only pumping to prevent flooding and ventilation for safety being allowed.