Cobalt Nickel Gray Periclase, an inorganic pigment, is a reaction product of high temperature calcination in which Cobalt (II) Oxide and Nickel (II) Oxide in varying amounts are homogeneously and ionically interdiffused to form a crystalline matrix of periclase. Its composition may include any one or a combination of the modifiers Al2O3, CaO, Cr2O3, FeO, Fe2O3, MgO, MnO, SiO2, TiO2, ZnO, or ZrO2.