A methodology for timing interventions made on the polychrome decorations of the façade of the Palace of King Peter I, the Royal Alcázar of Seville, Spain

A chronostratigraphic approach was used to the study of pictorial layers from the polychrome decorations on the façade of the Palace of King Peter I (the Royal Alcázar of Seville, Spain), to identify the timeline of successive decorative interventions made over time. Stratigraphic and mineralogical studies enabled the identification of modifications made to the artwork, either due to deterioration or to the various interventions made for maintenance purposes. The study of documentary references was accompanied by painstaking fieldwork and diverse laboratory techniques to establish stratigraphic correlations between the different areas and decorative elements of the façade. Future restorations oriented to the long-term conservation of this building (both preventive or of remedial nature) should take into account that the general appearance of the façade at present is close to that of medieval and modern times with the exception of minor modifications made during the intermediate interventions as result of an erroneous interpretation of previous chromatic alteration in specific areas of the façade.