High density sub-microcrystalline Ce0.8Gd0.2O1.9 (CGO) ceramics using an unconventional two-step sintering (TSS) process have been successfully obtained. Impedance spectroscopy has been used to measure conductivity of CGO samples between 283 and 422 A degrees C. The CGO ceramic samples sintered using the TSS process have been found to deliver superior physical and electrical properties compared to those processed employing the single-step sintering process.