Escalating inter-union violence in South Africa's mines and a likely difficult round of wage negotiations in the platinum, gold and coal sectors bode ill for the economy and social stability. Africa,Congress of South African Trade Unions,Jacob Zuma,Labor Issues,Lonmin,Marikana,Mining,National Council of Trade Unions,National Union of Mineworkers,NUM,Rustenburg,South Africa,Trade unions in South Africa,Paul Maidment