Sinop arkeolojik günlük seramiklerinin kimyasal karakterizasyonu

ABSTRACTCHEMICAL CHARACTERIZATION OF SINOPEANARCHAEOLOGICAL COMMON WARETUĞBA ARZU ÖZALM.S. in ChemistrySupervisor: Prof. Dr. Hasan N. ErtenAugust 2004Chemical characterization of archaeological common wares is important inorder to make quantitative explanations about history and trade relations of nations.Chemistry uses a microscopic point of view by applying spectroscopic methodsrather than macroscopic studies that archaeologists usually deal in the structuralanalysis. The present study is done on the common ware samples which were madeof raw clays from Demirci, Sinop, Black Sea Coast of Turkey, because of thegeopolitical importance of this region having trade routes.Elemental and mineralogical analyses of the clay-originated common waresamples found in the archaeological excavations and of the clay taken from Demirciregion, which locates at almost 15 km southern of Sinop, were made. While theelemental compositions of the samples were obtained by the spectroscopic method,X-Ray Fluorescence (XRF), the mineral structures were investigated by Powder X-Ray Diffraction (PXRD) and Fourier Transform Infra Red (FT-IR) spectroscopiciiimethod. Furthermore, the characteristic reactions (dehydroxylation, decomposition,transformation) that the clays experienced between the temperatures 50 and 1000 oCwere determined by Thermal Gravimetric Analysis (TGA). Characterizations of theSinopean samples were made and the similarity and differences between othersamples from different regions were investigated. Besides the provenancecharacterization, the distinctions between the production and firing techniques wereobserved.In addition to the experimental studies, chemometric techniques usingstatistical methods such as the standard clustering method and principal componentanalysis (PCA) was also applied to identify the groupings in the set of samples.As a result of this study, it is observed that the raw clays and ceramic sampleshave minerals of montmorillonite, quartz, feldspars, pyroxene, calcite and hematite atdifferent amounts. From the mineralogical and elemental data, it is concluded that thecolor variations are resulted from the calcium element occurring in pyroxene mineral.In the light colored samples, amount of this element and mineral is high whereas it islow in red colored ones.From the interpretation of elemental data by statistical methods, it is observedthat a classification among the Demirci samples is possible according to the functionof the pottery. In addition, classification among ceramics from two different regionsis possible by the interpretation of chemical analysis, even though the ceramics havethe same morphological properties of the same period.Keywords: X-Ray fluorescence spectroscopy, Powder X-Ray diffraction, Thermalgravimetry, Fourier transform infrared, common ware, Cluster Analysis, PrincipalComponent Analysis, Sinop, clayiv