Chromitites of the Akkarginskiy massif (the Southern Urals)

We consider the geological features of ultramafic rock and chrome ore deposits. It is shown that all studied deposits are podiform in morphology that is typical for the ophio-lite ultramafic rocks. Morphological and chemical features of the accessory and ore-forming spinels are described. Accessory chrome spinels from ultramafic rocks are mid-dle-Cr and high-Cr in chemistry (>42% Cr2O3). All studied ore-forming chrome spinels from deposits in the Main Ore Zone are high-Cr (54-63% Cr2O3). Some middle-Cr ore-forming spinels were found in deposit of the East Ore Zone (48% &2O3). We adduce a proof of the tectonic origin of present-day structure of the Akkarginskiy massif and its chrome ore deposits.