Mössbauer spectroscopy of ${}_{}{}^{57}{}_{}{}^{}\mathrm{Fe}$ in ${\mathrm{Y}}_{1\mathrm{-}\mathit{x}}$${\mathrm{Ca}}_{\mathit{x}}$${\mathrm{Ba}}_2$${\mathrm{Cu}}_{3\mathrm{-}\mathit{x}}$${\mathrm{Fe}}_{\mathit{x}}$${\mathrm{O}}_{6+\mathit{y}}$ for x=0.09 was used to study the site distribution of Fe in oxygen-rich and oxygen-reduced samples. In the superconducting sample (y=1) (${\mathit{T}}_{\mathit{c}}$=85 K) more than 90% of the Fe resides in the Cu(1) site. For y=0 the Cu(2) site orders magnetically at ${\mathit{T}}_{\mathit{N}}$=425 K. Based on the typical behavior of Fe in the magnetic Cu(2) site, we find that about 80% of the Fe occupies this site, thus we prove migration of Fe from Cu(1) to Cu(2) sites during depletion of oxygen at elevated temperatures. The spectrum above ${\mathit{T}}_{\mathit{N}}$ is smeared because of a distribution in the quadrupole interactions.

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