Cement copper was flash roasted in a vertical tube furnace to convert the copper to acid-soluble oxides as part of a postulated process for refining cement copper by oxidation roasting, acid leaching, and electrowinning. The results of the study showed that the oxidation was a linear function of oxygen concentration between 0 and 20 percent, but above 20 percent oxygen there was no further increase in oxidation. Therefore, air was the optimum oxidizing atmosphere in this flash roasting system. The oxidation followed a parabolic rate law as the roasting temperature was increased from 400 deg to 800 deg c. Extrapolation of the data, based on the parabolic law, indicated that at 400 deg, 500 deg, 600 deg, 700 deg, and 800 deg c, the roasting times required for complete conversion to soluble oxides were 75, 37, 21, 7.7, and 4.6 Seconds, respectively. Cyclic-roasting test results did not substantiate the predictions obtained through data extrapolation.