The Bureau of Mines investigated the flotation responses of two copper-nickel ore samples from the duluth complex with the objective of recovering bulk sulfide concentrates. One of the ores studied was taken from a test pit; the other was taken from a test shaft. The samples were quite similar except that the pit sample analyzed 0.35 pct cu and 0.11 pct ni and the shaft sample analyzed 0.69 pct cu and 0.14 pct ni. Flotation responses were studied in both laboratory and pilot plant tests. Pilot plant flotation responses were similar for both samples resulting in grades of 12.2 pct cu and 2.5 pct ni for the pit sample and 12.2 pct cu and 2.1 pct ni for the shaft sample. Weight recoveries were 2.5 pct for the pit sample and 5.2 pct for the shaft sample. Copper and nickel recoveries for the pit sample were 87 and 62 pct, respectively, and 92 and 73 pct for the shaft sample. Both concentrates contained small but significant values of cobalt and precious metals. Cobalt recoveries were low-- less than 40 pct for both concentrates. Precious metals contents of the concentrates were 1.59 Oz/ton for the pit sample and 0.99 Oz/ton for the shaft sample. Silver was the predominant precious metal by weight, but platinum and palladium represented the highest values.