The liquidus of the system Cu<sub>2</sub>S - Nd<sub>2</sub>S<sub>3</sub> - EuS
The position of the fields of the initial crystallization of the stages in the system Cu<sub>2</sub>S - Nd<sub>2</sub>S<sub>3</sub> - EuS: γ-Cu<sub>2</sub>S, β-Cu<sub>2</sub>S, EuS, EuNdCuS<sub>3</sub>, γ-NdCuS<sub>2</sub>(EuNd<sub>2</sub>S<sub>4</sub>), NdCuS<sub>2</sub> is determined on the basis of the phase diagrams forming the triple system Cu<sub>2</sub>S - Nd<sub>2</sub>S<sub>3</sub> - EuS and on the basis of the phase diagrams of the sections Cu<sub>2</sub>S - EuNd-CuS<sub>3</sub>. The succession of changing of the binary eutectics in the interior part of the triangle is established. The isotherms of the surface of the liquidus are constructed.