Reliquary medallions from the casket

On the fronts of the box and the upper body of the lid of the chest there are oval rock crystal reliquary medallions painted imitating grisaille enamel, with a window on the front and framework of gilded silver with smooth convex mouldings. These pieces are mentioned for the first time in Pedro de Madrazo y Kuntz's description of the chest in his work Navarre and Logroño, where he confuses them with enamels. There are fourteen medallions depicting the Annunciation, Saint Agatha, Saint Mary Magdalene, an unidentified Saint, probably Saint Helen, Saint Sebastian, two Calvaries and two scenes from the Stigmatisation of Saint Francis of Assisi. Five pieces have lost their original iconography, two of them being replaced by modern lithographs depicting the Rest on the Flight into Egypt and the Exaltation of the Cross. All the medallions have the same outline, with a central scene composed of figures in the foreground, surrounded by a schematic border of ovals and lozenges, with very simple gilded silver encircles. They measure around 6 x 5 cm and were made in Milan in the first decade of the 17th century. The rock-crystal plates are meticulously miniaturised on the reverse, using a technique that consists of painting in reverse, so that the motif is shown in positive on the plate. Since the colours are painted in reverse, in reverse succession, using pure colours, the order in which they are placed on the support is reversed. First the outline is drawn, then the details, painting in layers, with increasingly larger backgrounds, tracing the background of the scene last. The tones used are grey, both for the clothing and the flesh tones, and red tones for the backgrounds, complemented by the use of gold, which lends luminosity and richness to the overall composition. Colour is used extensively in subtle superimposed glazes, in schematic compositions, especially in the figuration of the landscapes in which the figures are set, which are not very realistic. This technique has been incorrectly referred to as verre eglomisé, which is in fact a technique typical of glass work .