I only know of a local website which lists jobs in Mauritius only and it is:http://www.myjobs.mu
I think there are only a few such companies outsourcing HR to Madagascar simply because some local big companies have branches there. You could still try like Price Waterhouse Coopers e.t.c
I haven't really seen any mining related jobs posted to be honest. The only jobs outsourced to Madagascar and maybe some parts of Africa relate to the Sugar Factories built there when part of the industry in Mauritius collapsed when we lost our European Union Single Source Sugar Export preferential rate agreement.