MADRID.- The Museo Nacional Thyssen-Bornemisza presents the results of the restoration and technical study of one of the most iconic works in its collection, Caravaggio’s Saint Catherine of Alexandria, carried out with the collaboration of Asisa.

Having undergone treatment in the Museum’s workshop, the painting is on view in room 11 in a display designed by the Restoration Department. The show includes X-ray images and infrared reflectograms which illustrate the most interesting aspects of the work performed, explain the methods used, and attest to the excellent quality of the painting. It also features a video of the entire restoration process, the most significant discoveries, and interesting details of the painting.

With this exhibition the Museum, aware of the interest aroused by restoration work, sets out to familiarise visitors with the working methods used by restorers, who are essential to deciding on the most appropriate treatments in each case and a source of important information for art historians. Knowledge of the techniques and materials used by artists is essential to be able to decide on which processes to use to halt the deterioration of artworks. Discovering the most intimate aspects of artistic creation furthermore provides an insight into the artist’s mind and period, as well as better-grounded arguments for understanding the creative process.

A fundamental work in the history of art
Faithfully based on one of Caravaggio’s usual models, Saint Catherine of Alexandria (c. 1598‒99) is a timeless depiction of beauty in keeping with the finest portraiture tradition. Instead of being shown in a mystic trance, the saint turns towards the spectator, establishing a direct rapport by means of her gaze. Fillide Melandroni, a young courtesan close to the artist’s circle, is shown dressed in the fashion of the day: a white blouse with wide, loosely gathered sleeves and a gold-trimmed neckline, and a purplish-grey bodice or dress adorned with wider braid of gold thread on the straps and front.

The saint is kneeling on a red damask cushion, her body tilted to the right and leaning on the breaking-wheel, a symbol of her martyrdom. A sumptuous blue cloth of considerable weight and thickness hangs from the wheel axle. Her reddish hair is partly loose, hanging over her shoulder, and partly gathered at the nape of the neck. Her hands delicately clasp a sword whose tip is tinged with red in allusion to spilled blood – or possibly a reflection of the cushion on which the figure is reclining.

The iconographic elements associated with sainthood and martyrdom include a palm positioned across the tip of the sword, creating the illusion of a scythe, and a halo in gold applied over the dark background above the saint’s head.

The light that falls directly on the young woman plunges the rest of the scene into semidarkness, accentuating the sensation of chiaroscuro and affording her an overwhelmingly powerful presence. The whites of the blouse and the pale flesh stand out against the background, creating a three-dimensional effect. This effect was repeated by the painter in many other works and it marked a technical innovation that was imitated by countless contemporaries of his and successive generations.

Restoration and technical study
The restoration of Saint Catherine of Alexandria focused chiefly on the complex task of removing the various layers of varnish applied over the years. Cleaning has restored the aesthetic unity and intensity of the original chiaroscuro. The movement of the volumes, the subtlety of the flesh tones and the delicacy of the textures have likewise been recovered. As a result, the painting has regained its balance and is much closer to its original appearance. The microsamples taken made it possible to identify and analyse the materials used by the painter and their condition and, thanks to gigapixel images and macrophotographs, the slightest alterations and details of the painting were observed. The photograph taken under raking light shows the surface of the canvas in which the relief and different textures are clearly visible. It makes it possible to see with greater precision the incisions in the imprimatura layer indicating the position of the volumes of the composition. This procedure is characteristic of Caravaggio’s technique.

Notable among the microsamples is a deep red layer. It relates to the first version of the dress, which the painter decided to replace with a duller greyish colour. The reason for this change is not known, but it is plausible to think that the client (Cardinal Francesco Maria del Monte) wanted the young woman to be dressed with greater restraint and discretion. The violet-blue layer of the final dress contains a mixture of lapis lazuli, grains of azurite, cochineal red, charcoal black, lead white and earth pigments. Lapis lazuli is also present in the cloth, mixed with finely ground charcoal black. The presence of this semiprecious stone indicates that Caravaggio had support and the means to acquire the finest materials for this commission.

X-radiography:
The X-ray image reveals subtle modifications. The most significant were made in the young woman’s hands. The artist initially painted them higher and subsequently altered their position. Numerous fingers are visible around the left hand, as the artist tested various possibilities until deciding on the position visible in the final work. It can also be seen that the painter sketched the complete circumference of the wheel in order to fit it into the composition and then painted over the part which, according to the account of the miracle, broke when the saint touched it.

Infrared reflectography:
This type of light reveals the corrections – known as pentimenti – the artist made throughout the creative process as well as the strokes used to emphasise or include a particular feature over areas that were already painted. The reflectogram shows the different position of the fingers beneath the final appearance, as can also be seen in the X-radiograph. In addition, the sword and the upper part of the wheel, painted later, show up in the reflectogram with a different intensity owing to the use of a large quantity of lamp black