Múzeumi műtárgyvédelem 2., 1975 (Múzeumi Restaurátor És Módszertani Központ)

Szalay Zoltán: Újabb adatok az üveg romlásához

Zoltán Szalay:

FURTHER DATA AS TO THE PERISHING OP GLASS

Summary

In connection with his study "The Reasons of Glass Perishing" the author describes his corrosion testing results from archaeological point of view. In course of the testings he observed the location of the object in the grave and its distance from the corpse and from the earth surface. He prepared a collodion impression (replica method) of the surface transformations. Embedded into glycerol this was tested through a phasecontrast microscope. Simultaneously the soil residues sticked to the glasses were examined with the Szelényi microanaly- tical method concerning their ammonium- and phosphate quantities, with the modification that the disturbing effects of the soluble silicates were prevented by tartaric acid. After having compared the data, the author arrived to the conclusion that the perishing of glass is in connection with the localization of the object in the grave. Those glasses were in the relative worst condition which were found near to the internal organs, while those ones which were near to the head and feet, were in better condition. According to the chemical analyses this phenomenon is connected with the enriched ammonia and phosphate contents of the soil. The two agents are separately less effectively corroding than both together. The pH value of the soil does not influence significantly tne perishing of the glass.

See tables III/12-V/36.

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