The oxidation of Mond nickel was studied between 1000° and 1200°C at oxygen pressures from . The oxidation rate was controlled by diffusion through the oxide and had a gross activation energy of . Least squares straight line fitting over the entire pressure range indicated the rate was proportional to . However, the rates above 1 atm appeared insensitive to pressure. On this basis, the measured rates below 1 atm more closely follow the dependence expected from electrical conductivity studies in . The oxide oriented in a preferred manner with 100 planes parallel to the polycrystalline nickel base.