The increased CaTiO3 precipitation after significant BaZrO3 dissolution (Figure ) indicates that the presence of Zr 4+ -ions in the BCZT matrix reduces the Ca 2+ -solubility. A similar effect was proposed in the early work of McQuarrie and Behnke , but could later not be replicated . This was tested by synthesizing Ba0.82Ca0.18TiO3 (BCT) and comparing the fractions of precipitated CaTiO3 with BCZT (see Table and Figure ). The precipitation of CaTiO3 in the BCT sample closely matched the expected amount based on the phase diagram by Devries et al. , while the w% of precipitated CaTiO3 in the BCZT sample was more than tripled (1.64 w% compared to 5.65 w%; see Table ). This confirms the reduced solubility of CaTiO3 in the BCZT matrix after the inclusion of BaZrO3, which could be related to the less favorable Goldschmidt tolerance factor of CaZrO3 . However, further research is needed to fully explain this phenomenon.