South Africa's Northam Platinum has said it is losing 1,500 ounces of output per day after it closed a shaft due to an accident that killed two miners.
Around 5,000 workers went on strike at the company's Zondereinde mine on 29 July to protest safety measures following the accident.
Northam Platinum spokesperson Marion Brower said the company is still investigating the cause of the accident, which was triggered by a fall of ground, according to Reuters.
Meanwhile, South Africa’s National Union of Mineworkers said the work stoppage was a warning to mine owners that they must improve safety.
Northam produces 300,000 ounces of platinum group metals annually.