Prékopa Ágnes (szerk.): Ars Decorativa 31. (Budapest, 2017)
Veronika SZILÁGYI: Rebirth of the Gundel Centrepiece: Methodological Experiments in the Restoration of Enamelled Metalwork
themselves. It was therefore opportune to explore new methods. The new method I experimented with was to use supplements made from a material that is similar to the original (not plastic), but which can eventually be removed, and which is therefore perfectly compatible with the ethics of restoration. The restoration process—preliminary inspections The preliminary inspections were carried out in accordance with the usual procedure for restorations: naked-eye and microscope examinations were followed by technical investigations. Even before the item was dismantled, X- ray pictures21 were taken, which facilitated a more precise understanding of the hidden structural components. In addition to revealing how the different elements were joined together, the X-rays also showed up a crack running along the metal backing of the shell-shaped, enamelled dishes. This investigation also provided information about which parts are hollow and which are solid, where soft soldering was used to enact repairs, and how stable the soft soldering was. Ultraviolet photography revealed previous enamel repairs and supplements, different layers of coatings, and traces of adhesive. The composition of the protective coating on the painted surfaces of the candelabrum, which seemed to be oil- or resin- based, could also be specified more precisely using this test, as well as microchemical testing. A handheld X-ray fluorescence meter (XRF)n also contributed to a better understanding of material compositions (such as the thickness of the gilding). This was useful in selecting the materials for treating the surfaces and in identifying the components of the enamel. The use of electron beam microanalysis (SEM-EDS) to examine samples taken from certain components of the centrepiece also assisted with material analysis. Comparisons of the data obtained in this way with the measurements taken using the handheld XRF meter revealed a number of discrepancies, which may be explained by the build-up of foreign materials on the surface and by the thickness of the gilding. Two types of procedure were used to identify the manufacturing techniques: non-destructive X-ray diffraction examination of texture and residual stress,24 and metallographic analysis, which required samples to be taken.25 The former method has only recently begun to be used for examining artworks. The advantage of this method is that it is non-destructive, although its weaknesses are that at present there are insufficient comparable results available, and that—by virtue of its surface measurements—the result can be affected by other factors (such as polishing). The metallographic analysis, involving samples and aimed at a more thorough examination of the manufacturing technique, was carried out in the same laboratory in Miskolc. The technical investigations did not produce a conclusive result in every area, but by comparing them it can be assumed with a high degree of probability that the smaller components (such as sheets with granulation and filigree and the hemispherical filigree ornaments) were made using electro- typing, (Fig. 4) while the larger ones (the dish, the rim decoration, the putti) were 115
