<Original Papers>Identification of Chromite Recovered from High Chromium Laterite Ore by Pyrometallurgical Treatments

Present investigation was conducted to identify the chromite recovered by various pyrometallurgical treatments reported in the previous work by microscopic examination, electron probe microanalysis and X-ray diffraction. The results obtained are summarised as follows : 1) The form and composition of chromite recovered by various preliminary reduction processes are the same as that of gravity concentrates except that of flow sheet A-25p which was recognised to possess higher Cr/Fe ratio with the reduction of FeO in (Mg, Fe) O (Cr, Al)_2O_3. 2) The composition of chromite recovered by treatments at high temperature depends on the oxygen potential of atmosphere and the iron and chrominum content altered in wide range. The reason was attributed to the mutual reaction with gangue mineral and goethite existing in fisher of chromite. 3) Under very low oxygen potential, the final reaction product from chromite was MgO・Al_2O_3. 4) The electron probe microanalysis with a thin section sample was a useful tool in clarifying the behaviour of chromite obtained in pyrometallurgical process