Technological characterization of polychromies on a Balearic medieval stone altarpiece of the 15th century

The objective of this research is to encrease the historical, artistic and material knowledge of the polychrome finishes in a medieval stone altarpiece within the context of the island of mallorca. There are many examples of Gothic art introducing polychrome finishes on stone sculpture, both in the religious and civil sphere in the Iberian Peninsula. In the Balearics, with the Christian conquest, this practice was also extended. The Passio Imaginis Altarpiece (1448-1453), located at San salvador Sanctuary in Felanitx (mallorca) has been studied. The characterization of the polychromies began with an organoleptic examination and photograph of general visible light and flush, assessed by digital image analysis (DIA). DIA allowed to reveal traces of polychromies that had not been detected by nacked eye in order to carry out the proper sampling. The samples were analyzed by optical microscopy (OM); scan electron microscopy (SEM-EDX), and the study of organic binders. The results obtained in the stratigraphic studies revealed the application of a sequence of layers with pigments employed in Iberian Peninsula. Binders detected are egg or animal glue. data indicates that it is most likely an original finish. Colour study contributes through the knowledge of the Passio Imaginis altarpiece and the awareness of its remains, to avoid the interpretation and/or destruction of the pictorial strata present in stone carvings.