Recent OPAL calculations have obtained significant differences in the Rosseland mean opacities compared with earlier Los Alamos work. These new opacities have had a favorable impact on several astrophysical problems, but the efforts have concentrated on hydrogen main-sequence stars or stellar envelopes. The present calculations consider carbon- and oxygen-rich mixtures. It is shown that for such mixtures the Coulomb corrections beyond the weak-coupling approximation are not negligible in the ionization-balance calculations when Rosseland mean opacities are computed. As for hydrogen-rich compositions, the hydrogen-depleted mixtures can show factors of 2-3 enhancements in the opacity compared with the Los Alamos results at temperatures of a few hundred thousand degrees