Abstract: In this paper a study of the system CaSO_4-PbSO_4 has been made using a high temperature microscope to determinethe solidus and liquidus temperature of mixtures of CaSO_4 and PbSO_4,and the phase diagram for the system constructed.Solid state reactions of mixtures of CaSO_4 and PbSO_4 at temperatures below the solidus temperature have been performedand a new compound,3CaSO_4·PbSO_4,has been found and subjected to differential thermal analysis to check for its re-versible transitions.

摘要： In this paper a study of the system CaSO_4-PbSO_4 has been made using a high temperature microscope to determinethe solidus and liquidus temperature of mixtures of CaSO_4 and PbSO_4,and the phase diagram for the system constructed.Solid state reactions of mixtures of CaSO_4 and PbSO_4 at temperatures below the solidus temperature have been performedand a new compound,3CaSO_4·PbSO_4,has been found and subjected to differential thermal analysis to check for its re-versible transitions.