Spectroscopic and thermal analysis of red clay for industrial applications from Tamilnadu, India

► Firing transformations of red clay were investigated by DT-TGA, FTIR, and XRD. ► Kaolinite, quartz, hematite, and goethite are presented in the red clays. ► The firing promotes the formation of new minerals such as mullite. ► FTIR technique is very suitable to analyze mullite environment. ► The studied clay has adequate characteristics for ceramic fabrication.