Archaeometric Investigations of the Chalcolithic Pottery from Topolița—Neamț County, Romania

Abstract

The current work deals with specific investigations on the ceramic fragment samples from the archaeological site of Topolița (Eastern Romania), which is essentially unexplored to date. X-ray diffraction (XRD) has shown that the ceramics contain quartz, berlinite, mica (muscovite), calcite, and opaque minerals, such as hematite. All evidence indicates the use of raw materials with a low limestone content (poor Ca clays) for the manufacture of these ceramics (Ca < 3.6%). The wavelength dispersive X-ray fluorescence (WDXRF) measurements indicated the presence of Al, Si, Fe, Ca, Zn, P, and K. All these data are well correlated with energy dispersive spectroscopy (EDS), which is used as an additional technique of scanning electron microscopy (SEM). Through thermogravimetry and porosimetry, some information have been obtained, with the results being correlated with the chromatic parameters that characterize the samples after burning: Various shades of color (red color with sparkles and partially or totally black interior), differently colored engobes, white pigment encrusted with white color from calcite, gypsum, clays, and quartz, as well as carbon deposits in the pores of the pottery, all specific to the Chalcolithic ceramics from this region. The recorded FTIR spectra of these samples led to the identification of calcite, quartz, gypsum, and aluminum phosphate, present as berlinite in all the pottery specific to this area. In addition, the presence/absence and the amount of specific chemical elements in the white pigments (e.g., calcium, aluminum, phosphorus, silicon, sulfur) could be used as indicative for the identified mineral compounds (XRD and FTIR). Calcite and silica-rich sediments as the primary decoration pigments, have been identified in this case.