Folia archeologica 23.

Ferenc Fülep – György Duma: Examinations of the Wall Paintings in the Cella Trichora of Pécs

CELLA TRICHORA OF PÉCS 21 I trichora and the plaster fragments found during the excavations extremely great similarities can be found. Sample 17 is exceptional as, despite its external characteristics, it is separated by its lime and silicic acid content (CaO

—Si0

2). From the point of its inorganic components it could be close to the lower layer of the wall paintings. Among the pieces of one colour listed in Group В we could observe at more than one that the plaster consists of two layers. The upper one with the paint is about 4-5 mm thick and can be comparatively easily separated from the lower mass of plaster. These two layers seem to be identical on the basis of inorganic quantitative analysis (samples 12, 13). Their identity was proved beyond doubt by spectral analysis. It bas become obvious that the two layers compared to each other and to similar plaster materials contain identical trace elements. The summary of these tests is given in Table III. As the derivatographic tests have yielded valuable data in other cases of plaster, therefore these analyses were done this time as well. At the thermic tests (DTA and TG) in most samples complex exothermic reactions accompained by loss of weight could be observed at comparatively low temperature. These tests have shown well that organic medium observed by microscope only in small quantities could persist in the plaster in rather significant amounts. Tbe organic medium content of plaster shows some difference among the samples, its average value is above 3 per cent. The percentage proportions of organic matter, silicic acid and lime content in the plaster are given in Table IV. With the graphic representation of the values given in the table the differences and relations of the individual samples can be clearly followed (Fig. 7

). It could be supposed upon outside observation that within the similarities of