Melting and thermodynamic properties of pyrope (Mg3Al2Si3O12)

The heat capacity of Mg₃Al₂Si₃O₁₂ glass has been measured from 10 to 1000 K by adiabatic and differential scanning calorimetry. The heat capacity of crystalline pyrope has been determined from drop-calorimetry measurements between 820 and 1300 K. From these and previously published results a consistent set of thermodynamic data is presented for pyrope and Mg₃Al₂Si₃O₁₂ glass and liquid for the interval 0–2000 K. The enthalpy of fusion at 1570 ± 30">1570 ± 30 K, the metastable congruent 1-bar melting point, is 241 ± 12kJ/mol">241 ± 12kJ/mol.