Thermal barrier coatings (TBCs) play an important role in gas turbines and jet engines by enabling higher operating temperatures that increase engine efficiency. The development of a TBC with low thermal conductivity, adequate mechanical toughness, and phase stability at high temperatures (>1300°C) will facilitate improved performance of gas turbines and jet engines. Currently, the commonly used TBC, 7 wt.% yittria-stabilized zirconia (7-YSZ), has low thermal conductivity and adequate mechanical toughness. However, when operated at temperatures above 1300°C 7-YSZ undergoes phase transformations that lead to a decrease in mechanical toughness and may result in the coatings detaching from the turbines. Thus it is crucial to develop a TBC that has improved properties relative to 7-YSZ. Yittria-, tantala-stabilized zirconia (Y-Ta-Zr) has many interesting attributes associated with it when investigating different compositions. Several compositions in the Y-Ta-Zr system were produced using co-precipitation to determine if any have the potential of exceeding the capabilities of 7-YSZ. This involved the use of indentation toughness tests to determine the material’s toughness and X-ray diffraction to study the crystal structure (phase) at higher temperatures. Certain compositions of Y-Ta-Zr show interesting characteristics when exposed to higher temperatures that may enhance the way TBCs work. The new generation of TBCs will produce advancement in air travel in jet engines on planes, and the generation of power through natural gas in gas turbines used by power generators.