Resistivity and percolation in a liquid/solid two-phase alloy

We calculated the resistivity of Au_1?xSi_x alloys in the regions between the liquidus and solidus temperatures where the system is a two-phase mixture of liquid and solid. The results are compared with the experimental data of Hauser, Ray and Tauc. The unusual behavior found in the Au rich region, where, near the liquids temperature, the temperature coefficient of resistance was found to be large and negative, can be explained in our calculation only if the size of the solid gold clusters becomes very small and thus limits the electron mean free path.