Abstract: Lanthanum zirconate (La₂Zr₂O₇, LZ) and La₂O₃-CeO₂-ZrO₂(LCZ) powders for thermal barrier coatings were prepared by coprecipitation. The chemical composition of the powders were analyzed by means of Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES). Crystallographic phases were determined by X-ray diffraction technique. Differential Scanning Calorimetry (DSC) was used to analyze the phase stability at high temperatures. The results showed that both LZ and LCZ powders kept the pyrochlore structure and there were no phase transformations for LZ and LCZ at high temperatures.