AMCU (the South African national union) president Joseph Mathunjwa addresses striking miners during a rally near Lonmin's platinum mine in Marikana on January 23, 2014. Tens of thousands of workers at the world's three top platinum producers were set to down tools today in a pay strike that could have a devastating impact in Africa's largest economy. Up to 80,000 workers at Impala Platinum, Anglo American Platinum and Lonmin mines will embark on an indefinite strike from early Thursday, after their demand to double the minimum monthly wage to $1,150 was rejected.  AFP PHOTO / ALEXANDER JOE        (Photo credit should read ALEXANDER JOE/AFP/Getty Images)