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The starting materials (Bi,O,, SrCO,, CaCO, and CuO, purity >99%) were weighed in, mixed, homogenized and calcined at 750°C for 24 h and subsequently at 800°C for 48 h to avoid the formation of a liquid phase. [I21 The calcined powders were pressed (625 MPa) and siutered for 24 h at 8 0 0 T SlO'C, 820"C, 83O'C, 840°C. 850°C and 870°C in air, respectively. Subsequently, the samples were reground, pressed and sintered at the same temperature for 60 h. Phase identification has been performed using a scanning electron microscope with EDX (Cambridge Instruments S 200), X-ray diffraction (Philips PW 1050, CuKa) and optical microscopy (Zeiss Axiomat) using polarized light. The freshly prepared samples were analyzed by emmission spectrometry with an inductively coupled argon plasma as excitation source (OES-ICP) to control the composition of the samples. No evaporation of Bi,O, was observed. The superconducting properties (T,) were determined by AC susceptibility measurements.