The Tashtab bentonitic clay deposit is located about 25 km southwest of Khur and Biabanak, Isfehan Province. This deposit is a product of alteration of ignimbrites with the age of early Eocene. Mineralogical examinations demonstrated that montmorillonite, saponite, quartz, nontronite, beidellite, microcline, anorthite, illite, albite, and calcite are the major mineral phases which are accompani...
