Diversified miner Xstrata
There's a limited impact on production at this stage, but customer deliveries have not been affected, a spokeswoman for the miner said, declining to elaborate on the precise impact on production or the number of workers on strike.
Members of the National Union of Metal Workers of South Africa (NUMSA) have been on strike at Xstrata Alloys Western Limb smelting operations since October 24, after a draft wage agreement was rejected by the union.
Employees have been on strike at its Boshoek, Rustenburg and Wonderkop operations. Operations are continuing to run at a reduced rate.
NUMSA said its members were demanding equal pay to Xstrata workers at the company's Lion ferrochrome smelter. The union said last week that the two sides were not currently negotiating.
The Boshoek smelter produces 240,000 tonnes of Ferrochrome a year, while Wonderkop furnaces and plants produce an annual 553,000 tonnes of ferrochrome. Rustenburg has an operational capacity of 430,000 tonnes of ferrochrome a year.
The three employ around 2,900 people.
NUMSA said in a statement it planned a protest march on Tuesday in the upscale shopping and office district of Melrose Arch to exert pressure to Xstrata's ruling oligarchy to accede to workers' demands.
(Reporting by Clara Ferreira-Marques, edting by Ed Stoddard)