Melting Relations of the Common Rock-Forming Oxides

Geological science is concerned with the nature of the materials of the earth and particularly with the processes by which earth materials have been changed and modified. Laboratory studies of the melting behavior of the common rock-forming oxides have been an important adjunct to the observations of the field geologist. For the past fifty years investigators at the Geophysical Laboratory have been obtaining quantitative information on the melting relations of many of the important rock-forming minerals. These studies of the fundamental chemistry of igneous and metamorphic rocks have yielded much information of value to ceramists, metallurgists, and mineral technologists. This paper summarizes the most important phase-equilibrium studies of unary, binary, ternary, quaternary, and portions of quinary systems of the common rock-forming oxides-SiO₂, Al₂O₃, FeO, Fe₂O₃, CaO, MgO, Na₂O, and K₂O.