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NiFe2–x Crx O4, 0 ≤ x ≤ 1.8, produced from appropriate oxides, has been studied using Mössbauer spectroscopy (MS) at low and ambient temperatures and in external fields up to 7 Tesla. X‐ray diffraction (XRD) shows all samples to be single phase cubic spinels, where a0 changes with change in x, as a concave curve, with a minimum at around x = 1. Analyses, based on Mössbauer spectra, show NiFe2–x Crx O4 to be a nearly perfect inverted spinel for x ≤ 0.6. However, for higher x ‐values the ordering is more complicated. It is shown that iron also populates the octahedral positions for x ≥ 0.8. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)