The synthesis of new compounds based on Bi2O3 is investigated because they can be used as new ecological inorganic pigments. Chemical compounds of the Bi2−xErx/2Zr3x/8O3 type were synthetized. The host lattice of these pigments is Bi2O3 that is doped by Er3+ and Zr4+ ions. The incorporation of doped ions provides interesting colours and contributes to a growth of the thermal stability of
these compounds. The simultaneous TG-DTA measurements were used for determination of the temperature region of the pigment
formation and thermal stability of pigments. This paper also contains the results of the pigment characterization by X-ray
powder diffraction and their colour properties.