Harmony Gold has begun to close three under-performing shafts in the Free State province in South Africa.

The affected units include the Harmony 2, Merriespruit 1 and Merriespruit 3 shafts at the Virginia mine.

In a statement, the company said these assets have no remaining payable reserves as they have reached the end of their lives and their closure has begun.

Harmony Gold, the world’s fifth-largest gold producer, said about 3,700 employees could be affected by the closure and it will consider transferring some to other operations in the group or propose early retirement.