Phase, Minero-Chemical and Microstructural Characterization of Chromite Ore

Abstract

Chromite ore sample was collected from active mine of Heroshah (34.503041 °N, 71.904565 °E) Malakand agency, Khyber Pakhtunkhwa (KP), Pakistan. The sample was properly washed, dried, and grounded to 74 m (200 mesh) in a pestle and mortar. The phase, microstructure and chemical composition of the ore was studied. X-rays diffraction (XRD) analysis revealed the presence of Aluminium chromite [Fe(Al,Cr)2O4] and Ringwoodite (Mg2SiO4) phases. Microstructural study revealed granular morphology where the chromite grains were surrounded by veins and grains of gangue material. It also shows fractures filled with gangue minerals. Elemental analysis confirmed the presence of high content of Chromium (43% on average) and iron (18% on average) in the as mined sample along with some proportion of Mg, Al and Si. Moreover, Fourier transform infra-red (FTIR) spectroscopy revealed the characteristic bands of chromium oxides (Cr+2-O-2).