Infiltration trials have been conducted by filling Cu tubes with ceramic powders and melting them under argon. No external forces were applied; successful infiltration of the ceramic relied solely upon favourable metal-ceramic wetting conditions. Oxides and covalently bonded compounds could not be spontaneously infiltrated but transition metal compounds such as NbC, Cr3C2, WC, NbB2 and Cr2N were. It was impossible to infiltrate any ceramics when oxygen was present in the system. Contact angle data in the literature were found to predict, with fair reliability, infiltration events in Cu-ceramic systems. The good correlation is thought to be due to the ease with which the oxide film can be prevented from forming on molten Cu during both sessile droplet experiments and infiltration processing.