The present work explores the possibilities of the application of Scheil–Gulliver equation in modelling the solidification of a real alloy. For this study, Cu-9 wt% Ni-6 wt % Sn alloy was chosen which exhibits profuse micro-segregation during solidification, and hence easy to quantify experimentally. Also, this alloy is spin odally strengthened high strength copper alloy and has industrial importance. In this study, thermodynamic assessment using Scheil–Gulliver solidification model was carried out. Subsequently, the assessed result was compared with the experimentally obtained results from energy-dispersive X-ray spectroscopy analysis, and a good agreement was observed between these results. Therefore, it could be concluded that the solidification of this particular alloy system can be modelled using Scheil–Gulliver equation.