Enhancement and recovery of the tiles affected by atmospheric pollutants in the Galleries of Punta Begoña, Getxo (Bizkaia)

Punta Begona Galleries, built in 1918 and located in the municipality of Getxo (Bizkaia, Spain) have a remarkable glazed ceramic decoration, whose current state of conservation presents an advanced level of deterioration. The study of the historical cultural property is framed within a multidisciplinary project, which aims to restore, recover and improve its historical and artistic value. In this sense, the recovery of the ceramic tiles is one of the crucial points, since it involves one of the visually most notorious elements. On the surface of the tiles, different degradations were observed, being the yellowish patina, one of the most significant. In order to carry out a cleaning treatment, the nature of the patina was evaluated, whose coating is a consequence of atmospheric contamination, as the chemical analyzes showed. Furthermore, a comparison was performed among four reactants both applied in reproduced pieces and in situ. To evaluate the effectiveness of the products, a quantitative evaluation was applied by colorimetry. In addition, this work shows an interdisciplinary methodology based on the scientific method as the best guide to achieve durable, safe and effective restoration methods.