Diagnostics and conservation of a gres work by Zauli placed in the Bucci park of Faenza

The main subject of this study is a glazed ceramic stele made by the sculpture artist Carlo Zauli from Faenza in 1986 and placed in the Bucci park of Faenza. The fgollowing degradation typologies were observed: crackings, lacunas, glaze microcracks and biodeterioration, being the crackings and the glaze microcracks the most evident phenomena. Therefore, a diagnostic study was undertaken aiming at the knowledge of the materials and their degradation causes, the definition of the better way of intervention, the monitoring of the behaviour of the erestored work of art. The formation of the fractures was attributed to the structural assembling using unsuitable materials like steel and cement, while the microcracks of the glaze can be attributed to the different thermal expansion of glaze and ceramic paste. So, it was decided to proceed to a preliminary in situ intervention, followed by a significant monitoring period, before the execution of the final restoration intervention. The consolidation and the fracture integration were carried out by using two different types of epoxy resin. After a two year monitoring time, the appearance of new cracks and the enlargement of the previous ones confirm that the fractures are mainly due tothe frequent dimensional changes of the various materials due to their different thermal expansion coefficients. In conclusion, a final intervention is judged necessary, which will be very different depending on the location of the stele: outside as it is now, or inside. In the first case a disassembly and a reassembling of the stele should be necessary, while in the second case a light intervention woulb be sufficient, but there would be a change in the possibility of enjoing the work of art by people.