We have grown Eu-123 single-crystal whiskers by annealing of precursor pellets containing Ca and Te. Microstructural and compositional analysis was performed on the longitudinal cross-section of a whisker and the area from where the whisker originated. Our observations elucidated some aspects of the growth mechanism from bulk precursor. While plate-like Eu-123 phase was observed in all parts of the precursor pellet, simultaneous precipitation and growth of some needle-shaped Eu-123 crystal is thought to be driven by the phase. The whiskers were annealed in different oxidation conditions and their formation of the residual phase (Ba, Ca)(3)TeO6 superconducting properties were studied by temperature dependence of magnetic susceptibility and resistivity measurements. (c) 2005 Elsevier B.V. All rights reserved.