Abstract Phase relations in the MgO–TiO 2 –SiO system have been investigated air a wide temperature range using equilibration method. X‐ray powder diffraction (XRD), scanning electron microscopy combined with wave length spectroscopy (SEM/EPMA), and differential thermal analysis used for sample characterization. Based on obtained experimental results, isothermal sections of at 1523 K, 1673 1773...