As camadas preparatórias na policromia tardo-gótica do retábulo mor da Sé Velha de Coimbra, por Jean d’Ypres

The original polychromy of the main altarpiece of the Coimbra Old Cathedral, produced by the painter Jean d’Ypres in 1501-1502, has partially survived hidden under three subsequent interventions. Analyses performed by Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy, micro X-ray Diffraction, micro-chemical tests and micro-Fourier Transform Infrared Spectroscopy enabled to demonstrate how particularly suitable were the materials employed and their implementation for the final effects to be achieved. This case-study, which involved the activity of Flemish artists in Portugal, allowed for a comparison to be drawn with altarpieces produced in Brabant at the same period.