Ali Abedini1* and Maryam Khosravi2
1Department of Geology, Faculty of Sciences, Urmia University, Iran
2Department of Mining Engineering, Isfahan University of Technology, Iran
*Corresponding author:Ali Abedini, Department of Geology, Faculty of Sciences, Urmia University, Urmia, Iran
Submission: August 05, 2022;Published: August 09, 2022
ISSN 2637-8035Volume4 Issue4
Karst bauxite deposits in northwestern Iran are part of the Irano-Himalayan bauxite
belt [1,2]. These deposits are similar to the Mediterranean-type karst bauxite deposits [3-
5]. The Saqqez region in northwestern Iran is one of the typical and interesting regions in
the world where bauxite deposits have undergone regional metamorphism. The Permian
bauxite deposits developed on limestone and dolomitic limestone bedrocks of the Ruteh
Formation have been affected by metamorphism processes. The bauxite ores show various
colors, including green, dark green, cream, greenish cream, grey, red, brownish red, white,
and yellow. Based on microscopic studies and XPRD analyses, the residual ores consist of a
mineral assemblage of diaspore, corundum, hematite, magnetite, goethite, rutile, paragonite,
margarite, amesite, berthierine, nacrite, chlorite, illite, montmorillonite, pyrophyllite,
chloritoid, muscovite, quartz, pyrite, anhydrite, ankerite, ilmenite, calcite, and dolomite. In
the Saqqez bauxite ores, paragonite, margarite, chloritoid, and corundum are the products
of regional metamorphism processes. The second latter minerals occur at conditions close
to the upper limit of the greenschist facies. It can be deduced that a mineral assemblage of
chloritoid-diaspore-kaolinite-magnetite-hematite in the northwestern Iran bauxite ores was
formed by the following reactions:
Kaolinite + 6Diaspore + Magnetite = 12 Chloritoid + 6H2O + 2O2
Kaolinite + Diaspore + 6 Hematite = 12 Chloritoid + 6H2O + 3O2
© 2022 Ali Abedini. This is an open access article distributed under the terms of the Creative Commons Attribution License , which permits unrestricted use, distribution, and build upon your work non-commercially.