From the specular X-ray reflectivity from an interface between two media one may derive the local atomic density distribution. In this work, models for the density profile across a solid-liquid interface are introduced. We concentrate on models in which the liquid is stratified near the solid wall. The calculations are compared with the measured X-ray reflectivity from the Ga-diamond(111)-2 x 1 interface. It appears that the liquid near the diamond surface already assumes a solid-like structure similar to that of the a-Ga phase.