Phase Equilibria in the System CaO‐TiO 2 –SiO 2

Results of a study of phase equilibria in the system CaO–TiO 2 –SiO 2 are presented. A prominent feature of the liquidus surface is a large two‐liquid region which appears on the equilibrium diagram as a broad band extending from the SiO 2 ‐CaO side to the SiO 2 ‐TiO 2 side of the triangle. Evidence for the liquid immiscibility and the significance of the resulting large high‐temperature liquidus region in silicate technology are discussed. Representative paths of crystallization of liquids in the system under equilibrium conditions are outlined. It is shown that solid solution in the system is virtually nonexistent except for the small‐scale substitution of Ti 4+ for Si 4+ in wollastonite. Indices of refraction of glasses are given. Composition and temperature are listed for the twelve liquidus ternary invariant points.