Maghemite has been found in samples from the lateritic 'buckshot ' ore bands of the Steep Rock Lake iron deposits. Partial chemical analysis of a magnetic concentrate gave 84. 42 per cent Fe 2o3, 0 . 36 per cent FeO, and 2.8 per cent H 2o. The maghemite has a cell edge of 8 .33 + . 01 A, and an average Vickers microhardness of 920. - Oxidation of magnetite to maghemite is relatively common but not abundant in magnetite-bearing iron ores and iron formations from a variety of geological environments. Maghemite forms as a rim on magnetite grains, or as irregular linear or cloud-like masses within them. There is apparently some relationship between maghemite development and polarmagnetism of samples.