Mining giant Anglo American Platinum said Thursday it was losing an average of 3,100 ounces of production a day since the beginning of a strike over job cuts last week.
Workers at two mines operated by the world largest platinum producer downed tool over plans to cut 3,300 posts.
"As a result of the strike action, an average of approximately 3,100 ounces of production per day have been lost," the company said in a statement.
The company said around 20 percent of workers had turned up at the firm's Rustenburg and Pilanesburg operations, in South Africa's platinum belt since the strike was called.
The majority of the striking workers belong to the militant Association of Mineworkers and Construction Union (AMCU).
Amplats said they continue to engage with the union "to try and return the business safely to optimal operation levels."
AMCU had called the protected strike after the company on September 2 handed 3,300 employees dismissal notices as part of a restructuring process to help return the firm to profit.
The strike-prone firm also announced that it would offer a further 1,600 workers voluntary severance packages.
The company has been hit by a number of stoppages since last year.