Document Type: Original Article
Department of Geology, Faculty of Basic Sciences, Sciences & Research Branch, Islamic Azad University, Tehran, Iran
Department of Geology, Islamic Azad University - North Tehran Branch, Tehran, Iran
Department of Economic Geology, Tarbiat Modares University, Tehran, Iran
Faculty of Earth Science, Shahid Beheshti University, Tehran, Iran
Department of Geography, Islamic Azad University - Ahvaz Branch, Ahvaz, Iran
Baba-Ali and Galali iron deposits are located west of Hamadan, within the Sanandaj-Sirjan geo-structural zone. Mineralogy and crystal-chemistry of the ore bodies using 57 analyses on the magnetite iron ore by SEM-EDAX method lead to some interesting results. Detecting the concentration of some trace elements such as V, Co, Ni, Cu, Cr, Ti, Au, PGE (Platinum Group Elements) and some impurities of S and P in the ore bodies indicates that only primary pyrites have concentrations of Pt. Other generations of pyrite and magnetite are depleted in these trace elements. The late stage of hydrothermal fluids that leads to mineralization of pyrite in calcite-quartz veins is important for Au mineralization and therefore pyrite is the best carrier for Au. Detection of abundant phlogopite crystals and trace element concentration patterns in the Galali iron ore has strengthened the acceptance of volcanogenic magnesium skarn type hypothesis.