A white preparation was applied in five successive layers. This is notable for its thickness, hardness and composition: it has a calcium carbonate base, whereas calcium sulphate was more often used in this region of Southern Europe. X-rays and the observation of the lacunae during the restoration did not reveal any cloth steeped in the preparation, such as is often observed in contemporary Provencal works. It was used to strengthen the cohesion of the support to limit the effect of the play of the wood on the paint layer, particularly around the joints and knots.
Detail of an infrared photograph
(C2RMF).
The underlying design is clearly
visible in the form of contour lines
and zigzag hatching.
Detail of X-ray (C2RMF).
A space was left on the Virgin's
garment where the head of the King
was to be painted. The X-ray also
reveals the traces of vandalism. The composition was laid out on top of a previously drawn design, and incisions were also used. The design, revealed by infrared reflectography, was executed on the preparation using a fluid substance to mark the outlines and to show the shading of the volumes with zigzag hatching. Small revisions are discernable in the features of the Dauphin’s face (eyes, nose and mouth moved). Incisions were made in the preparation to mark the edges of the fields of gold, in accordance with a technique traditionally used in the Middle Ages.
Other elements used to set out the composition were revealed indirectly by the X-ray analysis. Provision was made for the kneeling donors against the garments of the Virgin and Saint John, thus revealing that their presence in the picture was planned from the outset. Likewise, spaces were left in the landscape for the two coats of arms, proving that they were part of the original design.
Gilding, the first operation performed after setting out the composition, consisted of burnishing sheets of gold fixed by an orangey red undercoat, the colour of which is showing through in the worn areas. To simplify the procedure, the fleur de lys motifs were drawn in lozenges that were incised then gilded, and a layer of blue paint was added over the gold afterwards to define the shapes of the fleurs de lys. The gold leaf halos were decorated with a stamped pattern.
The actual execution of the composition was carried out using colours thickened with tempera (a binder made from all or part of an egg). The palette of colours identified during this study corresponds to the materials commonly used: lead-tin yellow (type I) on the yellow revers of Saint John’s cloak (before 1440); a pink layer for Christ’s flesh with surface shading provided by a brown glaze; azurite blue on a black undercoat for the Virgin’s mantle, Saint John’s robe and the drapery on the prie-dieux; a mixture of copper green and lead-tin yellow for the landscapes; bright red for the Virgin’s robe; and a mixture of white and red lacquer for Saint John’s robe, modulated on the surface with pure lacquer. Black shadows were used originally to accentuate certain elements of the composition such as the soldiers and horses in the background.
Crucifixion, details after restoration.
The revisions visible in the X-ray show that the white
h
orseman and the rider bearing the standard were
partially covered.
X-rays have enabled the identification of several revisions during the execution: the uncertain and confused image of the head of Christ shows that His position was changed; likewise, His body was enlarged on the right, slightly covering a small horseman in the background, and His left leg has been moved. The painter has also covered the horseman bearing the standard with the cloak of Saint John, giving it more fullness.