The chemical vapor deposition of hydrocarbons on porous zirconia (Z1O2) microparticles creates a reversed-phase support that is significantly different from conventional bonded reversed-phase supports. This carbon-overlaid zirconia support (C/Z1O2) is stable to conditions of extreme pH (0-12) and temperature (80 °C). It differs greatly from conventional supports in its chromatographic selectivity; the separation of positional isomers is facile, and they are well resolved compared to the separation on ODS silica. The unique chromatographic nature of this material was studied in detail to better understand and find applications for this novel stationary phase. The results of loading capacity and chromatographic efficiency studies are also discussed.