The Lennard-Jones solid equation of state (EOS), rooted in a Weeks-Chandler-Andersen approximation for the face-centered-cubic solid state, is found to reproduce Monte Carlo data for pressure and internal energy for spherical and freely jointed chain solids. This EOS is also found to correlate the melting temperature and pressure of argon, krypton, methane, and nitrogen and to predict the pressure-volume-temperature, heat of melting, and specific heat of argon and krypton. This EOS, when combined with a SAFT approximation for the liquid state, is found to correlate the solid-liquid equilibria of argon/krypton and argon/methane mixtures and to predict the solid-solid equilibria and the eutectic temperature of argon/methane mixtures.