A multi-analytical approach to the study of the mural paintings in the presbytery of Santa Maria Antiqua al Foro Romano in Rome

This paper presents the results of analyses carried out on three decorative phases of the pres- bytery of the church of Santa Maria Antiqua al Foro Romano in Rome: the fourth-century AD mosaics setting bed; the Adoration of the Cross, dated to the papacy of John VII (AD 705–7); and the paintings in the apse of the Pope Paul I (AD 757–68) phase. The research allowed the characterization of the painting techniques, pigments, organic compounds and degradation products by means of a video microscope, optical microscopy, and μ-Raman and FT–IR spectroscopy, contributing to a better understanding of the changes in the techniques and materials used throughout the centuries in one of the most relevant medieval Christian monuments in Western Europe