1) Bristol Isotope Group, School of Earth Sciences, University of Bristol, Wills Memorial Building, Queen’s Road, Bristol BS8 1RJ, UK, 2) Meteoritics and Cosmic Mineralogy, The Natural History Museum, Cromwell Road, London SW7 5BD, UK, 3) GeoZentrum Nordbayern, Universität Erlangen-Nürnberg, Schlossgarten 5, D-91054 Erlangen, Germany Geochimica et Cosmochimica Acta (2011), V75, pp7906–7925, doi: 10.1016/j.gca.2011.08.030 Confirmation of mass-independent Ni isotopic variability in iron meteorites Robert C.J. Steele (1,2), Tim Elliott (1), Christopher D. Coath (1), Marcel Regelous (1,2) We report high-precision analyses of internally-normalised Ni isotope ratios in 12 bulk iron meteorites. Our measurements of 60Ni/61Ni, 62Ni/61Ni and 64Ni/61Ni normalised to 58Ni/61Ni and expressed in parts per ten thousand (o/ooo) relative to NIST SRM 986. The precision on a typical analysis is 0.03o/ooo, 0.05o/ooo and 0.08o/ooo for ε60Ni58/61, ε62Ni58/61 and ε64Ni58/61, respectively, which is comparable to our sample reproducibility. We show that this ‘mass-independent’ Ni isotope variability cannot be ascribed to interferences, inaccurate correction of instrumental or natural mass-dependent fractionation, fractionation controlled by nuclear field shift effects, nor the influence of cosmic ray spallation.