In this paper we will apply a statistical mechanical theory of granular materials to a system composed of a mixture of elongated rods and spheres (both mono- and poly-disperse). We will show for a system of rods and spheres that the system's constituents do not completely phase segregate even at minimum close packing. The generalisation of this to packings of rods and bi-disperse spheres produces a similar result except that the two species of sphere do phase segregate at some particular packing.