"The night shift at the Kopanang mine didn't show up for work, nor did the morning shift," said AngloGold spokesman Alan Fine.

"It is a strike. An unprotected one."

The company had not yet received any communication from the striking workers or their representatives.

Fine said the mine had a staff of about 5000 workers and was responsible for four percent of the company's production.

Workers at Lonmin's Marikana mine, in North West, returned to work after a six-week long strike on Thursday, after rejecting union representation to hammer out a pay hike deal with their employer on their own.

The strike has since spread to other mines in the area, including a chrome mine, where workers also rejected union representation and chose to negotiate for themselves.

Earlier this week, a Business Day columnist wrote that other miners might not stand down until their wages are raised in a similar way to those of the Lonmin miners, and that this threatened to destabilise the entire mining industry.

The National Union of Mineworkers said on Wednesday that it was worried the Lonmin deal would lead to copycat demands.

NUM general secretary Frans Baleni said the union had been getting calls from members in the coal, platinum and gold mining sectors wanting similar increases.