Samples with nominal composition Bi1.92Pb0.32Sr2Ca1.7Mg0.3Cu3.07Ox were synthesized by solid state reaction. The results of XRD, SEM, EDAX and ac susceptibility measurement on the block and the power samples showed that in the samples there coexisted the 110K and 85K superconducting phases. The 2223 phase (110K) is considered to form at first at boundaries and in the outer region of the crystals of the 2212 phase (85K). We also believe that the origin of the structure of 2223 phase may initally exist in the 2212 phase grains and dact ad certain kind of stacking faults, and the 2223 phase finally forms and grows through the intercalation of the CaCuO2 layers in the crystal lattice of the 2212 phase together with climbing of dislocations. A calculation pased on experimental data supports this point of view.