The phase diagrams of the systems and and the densities of the liquid solutions have been measured over the permissible concentration and temperature ranges. Specific conductivities of the liquid mixtures have also been determined. The results indicate that the solutions, for concentrations up to about 30 m/o (mole per cent) and temperatures below 1000 °C, are essentially ionic conductors. Electronic conductance becomes evident for the more concentrated solutions. In the solutions, ionic conductivity appears to be restricted to concentrations below .