Using a dedicated technique, the superconducting region in the phase diagram of the Bi-Cd-Sr-Ca-Cu-O system is determined. Superconductivity above 85 K is observed for some compositions. X-ray analysis and scanning electron microscopy (SEM) on the superconducting materials are carried out. It is established that the materials are multi-phase, the prevailing phase composition being 2212. The addition of cadmium leads to an increase in grain size as well as in sample porosity. © 1991 Plenum Publishing Corporation.