What is a disadvantage of the mining industry in southern and eastern africa?

1) resources extracted by colonists (maybe less so now, but still) and so not available to the natives of the reason, going instead to China or whoever is doing the extracting now. 
2) Tough, dirty, dangerous job to do the actual mining. Tough - wears down the miners. Dirty - will cause long term damage, like black lung. Dangerous - both mining accidents and possible danger from dealing with the greedy.