Thousands of workers at South Africa’s Kumba Iron Ore mine on Monday embarked on a strike for better wages after pay rise talks collapsed, a National Union of Mineworkers (NUM) official said. Kumba, a unit of global miner Anglo American, said last week the strike will not significantly affect its production due to sufficient iron ore stockpiles. The NUM is demanding pay rises of between 7.5 percent and 10 percent on a one-year deal, depending on workers’ category, for its members at Kumba.