Folia archeologica 23.

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

208 F. FÜLEP - GY. DUMA carried out on the microscopic thin sections show great similarities among the different plaster samples. The main mass of the basic material is fine caustic sludge; in the basic material chalcedony in isolated patches and calcite in aggregates are visible. In its texture pits and groowes are characteristic, originating from plant ingredients that may be classified among typical cereals (belonging to the Gramineae species). The filling up of pits by mineral materials is rather limited in the form of thin filmy opaque sticking to the walls, more rarely in the shape of chalcedony and calcite films and veins. At some samples clay patches may be observed, in some places chalcedony gathers in the shape of rounded forms. The quantity of mineral fragments is generally small, in samples 2, 4 and 6 it is comparatively higher. As detrital component sand of fine granules (metamorphous and magmatic quartz), occasionally a granule of felspar, limonite in patches, and exceptionally pyrite granules could be observed. The spongy texture with pits (Fig. 6) seen at the microscopic tests interprets the extremely low volume of weights of these materials that average around 1,1. For sample 7 we defined, 1,10, for sample 10 1

,06 as volume weight. On the average samples of the plaster mentioned above quantitative chemical analysis was made. The results of these tests are summarized in Table I. The difference and similarity between the inorganic components of plaster materials is well expressed by their average CaO and Si0

2 contents. The summary of the average values is given in Table II. Inorganic chemical tests show that the upper layer of plaster covered by red paint of the cella trichora and the second layer of piaster below have differences that are not negligible, primarily in their lime and sand content. From the data of the analyses it has also occurred that between the upper layer of plaster in the cella