Chemistry of earth materials directs its applications, which enhances the science and technology of materials. Bentonite clay mineral belongs to the smectite group having wide range of chemical composition. Crystal size and chemical composition of clay is responsible for several properties and applications. In the present study, clay sample is collected from Gulbarga mine and is made active by acid treatment with sulphuric acid, nitric acid and phosphoric acid. The structure of the Bentonite clay before and after acid treatment is studied by X-ray diffraction study (XRD), morphology of the sulphuric acid treated clay is studied by Scanning Electron Microscope (SEM) and bonding of both before and after acid treatment clay is studied by Fourier Transfer Infrared (FTIR) tool. Cation Exchange Capacity (CEC) measurement is carried out for the clay before acid treatment and after acid treatment.