The Stability of Zirconia-Saturated Perovskite and Conditions in the Early Solar System

Perovskite and tazheranite (cubic zirconia) are among the most refractory oxides in nebular vapors [1] and important repositories for several refractory elements whose concentrations can potentially be used to constrain the environments of formation. There are numerous studies on the phase relations and thermodynamic properties of zirconias containing Al, Ca, Mg, Sc, Ti, and the REE [e.g., 2-4], but meteoritic zirconia is rare [5]. Meteoritic perovskite is much more common [e.g., 5-9], but there are few constraints on thermodynamic properties of the relevant solid solutions. Here, we describe experiments to determine the partitioning of minor elements between perovskite and zirconia of variable Zr/Ti; the results will be used to constrain thermodynamic modeling for the solid solutions represented by meteoritic perovskite.