JOHANNESBURG:  Sibanye Gold's Cooke mine in South Africa will remain shut until at least Thursday as the company goes through an appeals process for workers fired for taking part in a wildcat strike, it said on Monday.

Sibanye is losing 15 kg of gold production there per day, highlighting the social risks of mining in South Africa.

Spokesman James Wellsted said the company was concerned about the safety of its employees after receiving reports of threats of violence against miners not supporting the strike.

"We want to make sure the environment is safe for our employees," he said. Sibanye said last week it had fired 1,500 workers at the mine, which employs almost 4,000 underground miners, but they could appeal their sacking.

Workers at the mine downed tools almost two weeks ago, angered by a company drive to root out illegal miners which has included the arrest of employees for collusion.

Illegal gold mining has plagued South Africa for decades, with bullion pilfered from both disused and operating mines, and Sibanye has vowed it will clear all illegal miners from its shafts by January 2018.