Water is widely used in mining and minerals industry: for processing and transporting of ore and waste, minerals separation, dust suppression, washing of equipment, smelter refractory cooling systems and human consumption. Both economic and environmental considerations make the recycling and re-use of water an absolute necessity. The industry has made much progress in developing close-circuit approaches that maximize water conservation, and responsible management of water is a key ingredient in ensuring that mining companies’ contribution to sustainable development is positive over the long term. Common characteristic of mineral processing water is the presence of ions and chemical compounds with a high pollution potential. One of the most satisfactory ways of dealing with this problem is the total recycling of reject waters, but several technical aspects influence the extent to which recycling can be performed.