Limestone sculptures of the State Castle of Uherčice

• Carried out in: 2017-2019
• Location: The State Castle of Uherčice
• Origin: the 17^th century
• Material: Biodetric limestone the Lower Austria province
• Executed by students: Peter Majoroš, Adéla Machová, Stella Burkhardtová
• Teaching supervision by: doc. Jakub Ďoubal Ph.D., MgA. Petra Zítková
• Chemical-technology survey by: Ing. Petra Lesniaková, Ph.D.

 There is a set of limestone sculptures made in the 17th century at the Castle of Uherčice. The location of the set had changed several times. The sculptures deteriorated both due to the natural process of stone aging and repeated damaging effects of careless handling and vandalism. Several figures were preserved just as torsos. During the conservation works of the set in the 70s of the 20^th century, carved additions to the sculptures were used to replace some parts but not all of the sculptures were finished.

The preliminary survey of the set and the conservation treatment of the first few sculptures took place between 2017-18 within Peter Majoroš’s graduation Bachelor’s project. During the conservation works on Jupiter’s head, it was found out that the newly-added part of the head from the 70s did not match the original composition because the artist had not probably had the archive materials to follow – they were discovered much later during the survey. Because the difference was tremendous, the head was created according to the photo documentation depicting what the sculpture looked like in the period of the 20s-30s of the 20^th century. The reconstructed part was executed in artificial stone. There was a similar situation during the conservation treatment of two other sculptures of the set in the following academic year 2018-19. One of the sculptures, an armed man, had a carved addition which had not been finished and carved to the desired final form. Based on thorough investigation of the studies of the artworks as well as of historical materials, a connection between those two sculptures was found. They could have been created as a pair of guards looking like almost exact mirroring copies. The old additions were removed and a new head and hand were modelled of clay following the forms of the other sculpture. Then, silicone moulds of the additions were created and artificial-stone replacements were cast.

Finally, a complete conservation treatment of the sculptures was executed. The material of the sculptures carried signs of in-depth deterioration, therefore, consolidation was necessary. One of the contemporary-tested materials in practice was selected and applied for consolidation because it is suitable for deteriorated limestone. It was nanosuspension of calcium hydroxide, sold under name CaLoSiL E25, which can replace the lost binder of limestone and thus provides sufficient consolidation.

The limestone sculptures are going to be placed back to the arcades of the courtyard of the Uherčice Castle where they used to stand from the 30s of the 20^th century. In the following years, other sculptures of the set are going to be conserved as well.