Prékopa Ágnes (szerk.): Ars Decorativa 31. (Budapest, 2017)
Kornélia HAJTÓ: Restoration Options for Architectural Ceramics
6. Plaster model to replace an ornamental element on the Parliament building. It is an oversized positive plaster mould made to allow the contraction of clay. It is used to make a multi-part plaster negative into which the clay is pressed to form the piece. Zsolnay, Pécs 2012. Photo by Klára Csáki similar to those of some Pyrogranite pieces and makes a very stable bond to ceramic. By the addition of colouring agents, the colour may be adjusted to make a close approximation to the ground colours of different ceramics. The German company Keim has developed a complete system for the restoration of stone, exterior ceramics and faţades called Keim Restauro. The agents are used in series and cover every stage of work from cleaning to final surface protection. Remmers also provides a series that takes in every phase of construction restoration. The restorer can thus satisfy almost any demand—if the budget permits. A different approach is to make replacement copies of missing elements. We have frequently encountered the need to make copies of ceramic elements for exterior reconstruction work in recent years. In some cases, it was the original manufacturer, Zsolnay, which produced the replacements, but some developers have found the company unsuitable and commissioned another manufacturer. In 2012, for example, Zsolnay provided the missing ornamental elements in an internal courtyard of Parliament, (Fig. 6)7 but for the renovation of Várkert Bazaar that started the following year, copies of Zsolnay pieces that had deteriorated beyond repair were made by a different company. It is difficult for an outsider to follow the constantly changing situation in Zsolnay. Retouching Retouching is the process of correcting the colour of a surface where the appearance of the original surface, art work, building element, faţade or ceramic differs from that of an addition or patch. Glazed ceramics make up a special case. To ensure the visual homogeneity of the restored element, retouching is required to adjust the appearance, colour and surface shine of the patch or addition to the original glaze. Retouching involves painting with pigments mixed into a binder with special properties that have to be chosen for the purpose. In exterior applications, retouching is risky, because any surface layer not chemically bonded to the carrier surface may detach from it in the course of time. There are now special products to deal with this problem. 102
