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The calcination temperature was studied for optimum processing conditions for preparing (NdEuGd) BaCuO (NEG-123) and (NdEuGd)BaCuO (NEG-211) powders with good quality and fine size. This study used commercially available raw powders of NdO, EuO, GdO, BaO, and CuO in a purity of 99.9 % with 3-5- μm particle size. These raw powders were carefully weighed to have the compositions of NEG-123 and NEG-211 and pressed into pellets 25 g in weight. The samples were placed in a box furnace under ambient atmosphere and heated to temperatures of 820, 840, 860, and 880 C at a rate of 100 C/h, held there for 24 h, followed by cooling at 100 C/h. X-ray diffraction analyses showed that almost all the samples are single phase except NEG-123 processed at 820 C. The average particle size of NEG-123 powders increased with increasing processing temperatures, while that of NEG-211 remained in the same range below 5 μm irrespective of the treatment temperature. Since the particle size of NEG-123 powders was around 10 mm, one need to refine the particle size below 5 μm with a technique like mechanical grinding for the production of high J NEG-Ba-Cu-O bulk super conductors. NEG-211 powders will be suitable for such a use in the present form. The homemade powders were used to fabricate NEG-Ba-Cu-O bulk by cold top seeding melt growth with MgO seed following by oxygen annealing treatment. The characterization of bulk demonstrated critical temperature at 65 K with maximum critical current density of 70,000 kA/cm at 10 K with H//c-axis. [ABSTRACT FROM AUTHOR]