FT-IR and Micro-Raman spectroscopic studies of archaeological potteries recently excavated in Poompuhar, Tamilnadu, India

Abstract

Ancient ceramics are the abundant artifacts that give the knowledge of the past societies. Therefore it is of great importance to acquire knowledge about the chemical composition of the clay in archaeological artifacts. The spectroscopic techniques represent one of the most powerful tools to investigate the structure of all the materials and chemical composition of the cultural object like potteries. An attempt has been made in the present work to estimate the firing temperature of the archaeological pottery shreds excavated from the archaeological site Poompuhar in the state of Tamilnadu in India. The firing temperature of the archaeological pottery shreds were estimated by recording the corresponding FT-IR spectra in the range 4000–450cm−1 and Micro Raman spectra in the range 1800–400cm−1. The clay mineral present in the pottery samples are identified through FT-IR method and was confirmed with Micro Raman spectroscopy as both are complement to each other. The major primary mineral present in the samples is Kaolinite and the secondary mineral present is quartz and the accessory minerals present in the samples are hematite, magnetite and feldspar. The results of Raman spectra showed that the potters of this site used a mixture of clays as raw materials. The firing temperature for some of the samples did not exceed 800°C which suggests the use of open fire.