M. Járó - L. Költő szerk.: Archaeometrical research in Hungary (Budapest, 1988)

Analysis - BALLA Márta, BÉRCZI János, KEÖMLEY Gábor, ROSNER Gyula, GABLER Dénes: Provenance studies of ceramics by neutron actiwtion analysis

Analytical data of "Standard Pottery" Element Measured value (M) ppm Reference value (R) ppm M-R Element Measured value (M) ppm Reference value (R) ppm ppm % Sc 19.4 ±03 20.55 ±033 1.15 5.6 Cr 114 ±9 115.1 ±3.8 1.1 1.0 Fe 10750 ±140 10170 ±120 580 5.7 Co 13.7 ±0.6 14.06 ±0.15 036 2.6 Rb 70 ±6 70.0 ±63 0 0 Cs 8.9 ±0.6 831 ±0.55 0.59 7.1 La 47.5 ±04 44.90 ±0.45 2.6 5.8 Ce 83.0 ±6.1 8035 ±3.9 2.7 3.4 Eu 1.13 ±0.04 1.448 ±0.034 032 22.1 Yb 3.0 ±04 2.80 ±036 0.2 7.1 Lu 0.42 ±0.04 0.402 ±0.036 0.02 5.0 Hf 5.7 ±0.4 6.23 ±0.44 0.53 8.5 Ta 1.9 ±03 1.55 ±0.44 0.53 22.6 Th 15.0 ±0.8 13.96 ±039 1.04 75 U 4.4 ±0.5 4.82 ±0.44 0.42 8.7 whether their concentration changes systematically between the inner and outer surface of the pot or in the longitudinal direction. It may be supposed that volatile elements dissolve unevenly due to the temperature gradient between the inner and outer surfaces during baking. However the determination of these elements (e. g. As, Br) was disregarded in advance. In our opinion, for the examined elements the local differences arising from uneven distribution of accessory mineral ingredients and the mineral composition of argil can cause inhomogénéity. In this respect trace minerals well characterizing the geological environment such as zircon, biotite, quartz, feldpars can play an important role. It is supposed that the smaller the degree of local deviation, the more perfect the technology of preparation, i. e. the homogenization, sluicing and admixture of the basic material. Moreover, the finer and the more equigranular the product, the smaller the deviation of the elementary concentration. From the above, the following conclusion can be drawn. Investigations on homogeneity must be carried out on each type of ceramics because there are significant differences in the development of the technique of manufacturing and the standard of production. The same is true for the demands on the function of each piece (domestic pottery export goods). After having carried out investigations on homogeneity it can unambiguously be decided whether the deviation of the sherds calculated from the analytical data is significant or not. A sherd of greater size was selected from the type of pottery examined by us, then a sample was taken from the inner and outer surfaces and from fractures on 10 spots from each piece. Table 3 shows the relative standard deviations of the mean values in per cent gained by the analysis of 10 samples. Below the results of examination carried out on terra sigillatae and ceramics of the Avar age are introduced. The measured data can be seen in the Appendix.