To solidify a dispersion alloy with a miscibility gap in the liquid state, the two-phase immiscible region map have to be traversed. The composition and consequently the properties of the solid depend on the distribution of the minority dispersion phase. The distribution is mostly controlled by density segregation and convective how in the melt. Natural convection in a transparent model alloy of 65 w% paraffin oil and 35 w% benzylbenzoate was investigated with LDV and holographic interferometry. The benzylbenzoate-rich dispersed phase is the heavier component. The lighter paraffin oil phase was the majority component. A horizontal temperature difference was applied to the liquid layer with the cold side temperature below the phase separation temperature and the hot temperature above it. The liquid system undergoes phase separation when approaching the cold wall and dissolution when approaching the hot wall. Flow velocities at different locations in the test cell are measured and compared to density field visualizations. At small temperature differences the natural convection flow is time-dependent, due to the phase separation process.