Cordierite-garnet-sillimanite-quartz equilibrium: I. New experimental calibration in the system FeO-Al(sub 2)O(sub 3)-SiO(sub 2)-H(sub 2)O and certain P-T-X(sub H(sub 2)O) relations

Energy Fe-end member reaction depicts a positive dp/dT slope and its position is related to the water content of the equilibrium cordierite. The anhydrous breakdown curve has been constructed based on the determination of H2O content. The P-T position of the anhydrous curve varies depending on the context of H2O, which has been maximized and experimentally verified to be unity.