The warning came from Mineral Resources Minister Ngoako Ramatlhodi, who on Monday abandoned mediation efforts between the strikers and Anglo American Platinum, Impala Platinum and Lonmin.
“The situation is grave, the longer the strike goes on the more likely shafts will close,” Ramatlhodi told journalists.
“I suspect there will be job losses, realistically,” he added.
After months of standing on the sidelines, the government stepped in at the end of May to try to break the deadlock between the Association of Mineworkers and Construction Union (AMCU) and the producers.
Ramatlhodi said he had tried to put pressure on the companies and the union to reach an agreement but he could not prolong the negotiations.
“My main role has been to create an environment conducive for the parties to talk to each other again,” he said.
“I don’t think going on for much longer would have assisted.”
Some 80,000 miners stopped work on January 23 to back their demand that the minimum monthly basic wage be doubled to $1,180 (866 euros).
Counter offers by the mining firms have been rejected.
The strike has cost employers 22 billion rand ($2 billion, 1.47 billion euros) in revenue while workers have forfeited about 10 billion rand ($945 million, 695 million euros) in wages and benefits, according to industry figures.
It also helped push the South African economy at the start of the year into its first quarterly contraction since the global economic crisis five years ago.
Mining firms estimate the strike has already affected 45 percent of the global supply of platinum, which is used to make jewellery and catalytic converters in cars.