Triães, RicardoSantos, LuisCoroado, JoãoRocha, Fernando2021-09-182021-09-182014-041995-2635http://hdl.handle.net/10400.26/37521Wall tile panels were commonly used in recreational open outdoors spaces in 18th Century noble houses I Portugal. The nature of their location and the lack of maintenance of such spaces, which lost their purpose during the 20th century, contributed to their natural deterioration. In order to preserve one such panel and facilitate the conservation treatment, it was removed from its location and transported to the facilities of the Polytechnic Institute of Tomar, Portugal. The interest in studying this particular panel was prompted by the advanced stages of deterioration observed in some tiles, where natural succession of biological colonisation and weathering were registered as some of the main deterioration causes. Furthermore, the advanced deterioration stages indicate that removal was a necessary action, as natural weathering would lead to its destruction. The study involved a thorough analysis of the environmental characteristics of the wall placement, the wall materials themselves, the mortar, the ceramic body and the glaze. The methodologies used involved microscopic and laboratory testing to evaluate the extent of lichen colonisation and its influence in the loss of glaze and posterior deterioration of the ceramic body. Results indicate that natural and environmental characteristics, combined with substrate typology and micro-organisms, contribute to accelerate the deterioration process, though appropriate techniques of preventive conservation can be used in specific panels or broader situations. This study will enable the development of innovative methodological and technical approach to the conservation problem here portrayed.engjournal article2021-09-17cv-prod-1362715