Ce-2(C2O4)(3) . nH(2)O powder was prepared by adding oxalic acid to a cerium nitrate solution. Cerium oxalate was identified by chemical and thermal analysis, (DTA/TGA). Cerium oxalate powder was calcined to oxides at different temperatures and the powder properties (specific surface area, particle size distribution, mean particle size, bulk and tap densities) of these oxides were determined. X-ray diffraction (XRD) patterns of cerium dioxide powders obtained at different calcination temperatures were evaluated. The crystallite size was calculated both from XRD data using Sherrer's equation and from specific surface area data for each temperature. (Th0.95Ce0.05)O-2 powder was prepared by mixing the binary oxides. The compacted pellets were calcined in air at 1050 degreesC. The XRD patterns of these pellets were evaluated to characterise the formed solid solution. (C) 2001 Elsevier Science B.V. All rights reserved.