Of the church of Sant Pau de Esterri de Cardós, there remains both the decoration of the apse and the frontal altar that was presiding the major altar, dated in 1225 by an inscription. All the figures and the decorative elements of the frontal altar are done by reliefs of gypsum, which were covered originally with a cap of tin and a golden glaze called colradura. This technique, habitual in the frontals of Catalan altar, was seeking to reproduce with slightly costly materials the effects of relief and brilliancy of the frontal altar of goldsmithing. The loss of the gilding does not allow to understand, today, the vigorous aesthetic original effect.