Mineralogical Investigations of Shahid Nilchian (Dopelan) Bauxite Deposit

Shahid Nilchian (Dopelan) deposit, located in high mountains of Chahar-Mahal Bakhtiari Province within the Zagros Thrust structural unit, is one of the main bauxite and argillite deposits of Iran. Many highly folded and faulted sedimentary successions are cropped in the area. The bauxite of Shahid Nilchian deposit is of lateritic type and belongs to Permo-Triassic in age. Five bauxite types with different quality have been recognized in the area. Mineralogical investigations have carried out using thin and polished sections, XRD and XRF analysis. According to these studies, it is verified that the major minerals are diaspore and kaolinite. Anatase and boehmite has identified as minor minerals. Some other elements such as iron, zirconium and vanadium are also presented in different minerals. The main identified textures are brecciated and pisolitic. In its application as refractory material, minerals containing iron, silica and titanium are the important gangues of bauxite. The main objective of this mineralogical study is to identify the minerals of the above mentioned elements. It is concluded that kaolinite, anatase and different iron oxides are the main sources of these elements.