The stock ignored news from Zambia where President Edgar Lungu said he would not allow the firm to lay off workers at its Mopani Copper Mine, as it mothballs it for 18 months.
The drastic move makes of Codelco the mining company that has let go the highest amount of workers in Chile since copper prices began their decline over a year ago.
At least 1.6-million people live in informal settlements around Johannesburg, many of them on or near mine waste sites, plagued by illegal miners and controlled by armed bands.