ULUMA MINES LTD., KALULUSKI, NORTHERN RHODESIA: Mineralization Chalcopyrite, li and cobaltiferous pyrite compris- ing about 5% of the total ore, with quartz as the balance. Chibuluma is one of the few operations that produce a cobalt concentrate by selective flotation after making a copper concentrate. Chalcopyrite is floated a coarse grind of 10% +65 mesh from a lime alkaline pulp of pH 11.0. A high grade copper concentrate is produced from the rougher machines without cleaning. Copper tailings are conditioned first with copper sulfate to activate the cobalt minerals, then with acid to drop the pH to 9.0 for the flotation. Single cleaning of this concentrate produces the final cobalt con centrate. Tailings are classified in cyclones to produce sand for mine fill