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A ∑ = 11 {332} Ni bicrystal was grown by solidification. The Grain Boundary (GB) atomic structure studied by high resolution electron microscopy (HREM) has been shown to depend upon the position in the bicrystal of the extracted sample. Strongly correlated to the atomic structure, (GB) defects (GBD) have been characterized: all their Burgers vectors belong to the Displacement Shift Complete (DSC) lattice and the height of the step associated with each GBD varies up to a few nanometers. In the symmetrical and almost symmetrical GBs, at the head of the bicrystal, the dislocation cores can be well localized, whereas in the asymmetrical GBs, at the end of the bicrystal, their cores are much more difficult to localize on the HREM image. The influence on the GB structures of the impurity content which varies along the bicrystal is also discussed. [ABSTRACT FROM AUTHOR]