Single crystals of Zr-0.065 at% Fe (95% e), 5 7 Fe), from a common parent, have been studied by Mossbauer spectroscopy, using both transmission and conversion-electron modes. In the @'as grown@' state the Fe is present as the meta-stable phase, t-Zr 2 Fe. Vacuum annealing, in the range 795-973 K, results in gradual decomposition of t-Zr 2 Fe and the diffusion of Fe from the bulk to the surface, where it forms the stable Zr 3 Fe phase. The kinetics of Zr 3 Fe formation show fair accord with the known diffusion properties of Fe in α-Zr. Some results for other dilute Zr(Fe) single crystals are reported.