FULLN CHEMICAL enamel pigments Cobalt chrome blue FU-E512 is a blue green inorganic pigment for enamal. It's obtained by mixing, calcination and micropowder treatment of several or more combinations of raw materials such as zinc oxide, cobalt oxide, chrome green and alumina. During calcination at high temperature, zinc oxide (Zn2+), cobalt oxide (Co2+), chrome green (Cr3+) and aluminum oxide (Al3+) react with each other and uniformly diffuse to form a substance with spinel structure.