Mineralogy of clay deposits named Gel-E-Sarshour, mainly mined in CentralProvince, Tafresh area, has been studied. This material is mined from Oligocene Lower Red Formation in wells up to 30 m depth. Clay layers have different thicknesses from 1 cm to 2 m in different parts. It comes in olive green and has a soapy touch. The clay will change to paste if mixed with water and used mainly as shampoo as well as treatment for some of the skin diseases. Grain size analysis has shown that 92.3% of the material is <2μ. XRD, IR and chemical analysis have established that the main constituents of < 2μ fractions of Gel-E-Sarshour are: 91 % high layer charge, dioctahedral mixed-layered illite/smectite and 9 % kaolinite.