This project is a continuation of a series of studies that focuses on the phase equilibria and thermodynamics of important mineral systems. The current project emphasizes studies on biotite, ferrosilite, esseneite, Fe-Ti oxides, ternary feldspars, and Ca-Mg-Fe carbonates using reversed phase equilibrium experiments followed by thermodynamic solution modelling of the results. This research will ultimately have application in constraining the intensive parameters (e.g., temperature and pressure) under which igneous and metamorphic rocks crystallized.