Investigations of the ancient ceramic sherds excavated from Börükçü site in Muğla, south-western Turkey, by ATR-FTIR spectroscopy and statistical multivariate analysis

This paper presents the mineralogical characterization of 56 sherd samples from the Börükçü site in Muğla, Turkey. Principal component analysis (PCA) employing raw attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectra (825–400 cm−1) with 17 smoothing points discriminated the sherd samples into five different groups (A–E). The second-derivative ATR-FTIR spectra (two polynomial degrees and 11 smoothing points) between 1700 and 400 cm−1 were successfully used to assess the firing conditions. The obtained results showed that the firing temperatures are about 600–800°C for sherd groups A, C and D and about 800–950°C for sherd groups E and B.