Ultraviolet fluorescence made clear the interventions of previous restorers. Retouching was detected in the faces and robes as well as in areas of overlapping paint layers. Candle burns (caused by the flames of candles positioned close to the painting in its original context) were found at different heights, depending on the positioning of the candles. Over time, these burns were covered with plaster and retouched. Once these areas were identified, they were sutured up like wounds, and the old repaint and plaster was removed.
Infrared reflectography revealed that the preparatory drawing was made by tracing a cartoon (scaled-preparatory drawing) and then reinforced in some areas with strokes of watercolour paint. Infrared reflectography revealed the preparatory drawing made with tracing from cardboard and taken in a few areas with watercolour strokes. The idea of the composition originated in the notebook of the painter and could be developed on sheets of paper. Then, the entire composition was drawn again on cardboard, usually in full size, but sometimes in smaller size, split into smaller pieces of cardboard: this process was used by the painter to enlarge his sketch to the full-size of the final painting. The enlargement was done by cross-hatching both the paper and the cardboard, varying their size (three, four or even ten times larger). The reverse side of the cardboard was then blackened with charcoal, and the painter would trace the contours of the figures with a rounded stylus, applying pressure directly on the layer of smooth plaster applied on the wooden board, being careful not to rip the cardboard or to add too much pressure. When the cartoons were finally removed from the board, a majestic drawing came to sight. From a small drawing on paper, the painter could scale it up to full dimensions (three meters by two): a true miracle of art, as if the figures had swelled by themselves. Often, in order to make the tracing adhere better, a brush soaked in a small amount of water and glue was applied to the surface of the drawing, so that it would stick. The black strokes outlining the faces and defining anatomical parts such as mouths, noses, hands and feet are noticeable. Numerous "afterthoughts" on the feet of the figure on the left holding the dead Christ and on Christ's face are clearly visible. There is also a unique restlessness in the feet, which do not seem to stand still. This is perhaps a sign that the painter (with his decisive stroke like Pontormo) was looking for the perfect balance of the bodies in every minimum articulation in a work of great dynamism, in continuous circular movement.
The wooden support is composed of six planks. The planks retain an extraordinary flatness, in part because of the choice of support—the typical Tuscan wood, poplar—and the fact that Pontormo chose planks with a sub-radial cut (i.e. close to the pith), which were less subject to warp over time. During the preparation of the planks, some knots in the wood were removed and replaced with wooden dowels with linear, unrounded shapes. There is only one, slight split in the top right-hand corner. This split restored by inserting a small piece of poplar wood and glue. A permethrin-based biocide was brushed over the entire support to preserve the entire structure and to prevent against woodworm.
The colours and the underlying preparation presented no problems except for some slight lifting, remedied with micro-injections of acrylic resin. Some of the colours were originally brighter and have been compromised by past restoration attempts. One of the most important past restoration attempts was that of Otto Vermehren, who restored the work before its exhibition in Paris at the Exposition de l'art Italien de Cimabue à Tiepolo in 1935.
The cleaning was carried out with the help of wax emulsions and ketone solvents. The surface was massaged with soft brushes, gradually removing the yellowed varnish and old retouches and yielding the so-called "skin of respect” (any cleaning beyond this ‘skin’ would be detrimental to the original colors). After this cleaning, the original colours emerged, most notably the Madonna's mantle, which has regained its light blue even in the intermediate tones of light blue and light blue grey. The flesh tones have achieved their original rosiness and the robes, which were found to be generally well preserved, have recovered their original reds, oranges and greens. After removing the old retouches and the plaster and wax that covered the candle burns and woodworm holes, new gesso was applied using polyfill, plaster and glue. Losses were then filled and integrated. Tempera colours were used on the plasterwork and watercolours on the uncovered areas. These areas were further refined with a general varnishing with pure powdered pigments .A spray of same varnish was then applied to the pictorial surface, allowing the image to be appreciated in its entirety.PONTORMO'S PALETTE
The colours in the Deposition are soft, with light tones and shadows kept to such a minimum so that in some areas shadows seem non-existent. The colours are so bright and so similar in intensity that in some areas, such as the parts of the figures bathed in light, are barely distinguishable from the areas parts in partial or full shadow. Repeated selective chemical analysis of various colours revealed the use of egg tempera (a medium in which egg white and egg yolk are used as a binder for powdered pigments). Most mineral colours are mixed with lead white, i.e. the biacca. This technique, known for maintaining its chromatic intensity over time, explains why work appears so bright regardless of the source of the light (even if the light organized by Pontormo coming from the right), creating a very singular effect, striking or caressing the figures with minimal additions of white. Tones of blue and light blue prevail where azurite is mixed with white lead, but also with carbon black and with lapis lazuli, as seen especially in the Madonna's robe. The sky is composed entirely of lapis lazuli and white lead. The flesh tones are shades of pink, with white lead, cinnabar red and a little red earth. The curls of the hair, namely Christ's, are made with yellow and red ochre. The copper-based greens are mixed with white or lead yellow, as is cloth under the figure of the carrier. This last area is also now free of a previous restoration executed in so-called ‘copper resinate,' which made the folds appear darker. The figure’s garment, which covers his entire body like a tattoo, is composed of garanza lacquer and white lead with some shades of blue. Pontormo used different brushes; small brushes were used for minute details and large brushes for broad, more liquid applications of paint, which tend to overlap like fish-scales.
The earliest known restoration of the Annunciation dates to 1620, when a marble tabernacle commissioned by the Cardinal of Carprentras, a devotee of Saint Charles Borromeo, was added to the chapel. In this period the figures were partly repainted, to replace the areas that had been destroyed or demolished. These repaints were still present in 1964, when some of them were removed. In 1967, following the 1966 flood, the frescoes were detached from the wall and remaining repaints removed, finally revealing the fresco’s original composition and colours.
The fate of the frescoes originally in the dome, depicting the Eternal Father and the prophets, is a different story. These paintings were irretrievably during the ‘decapitation’ and rebuilding of the dome in 1766, which coincided with the decision to build a viewing gallery adjacent the Vasari corridor on the counter-façade. This new dome was decorated with perspective views by Domenico Stagi which, however, was later whitewashed, concealing it from view. Probably in 1972, in order to exhibit the Annunciation at the Firenze Restaura exhibition, the Masonite supports were partially demolished and re-glued to a new glass-resin support. There are reports that the Virgin Annunciate along made a trip to Japan for the exhibition Capolavori del Rinascimento Italiano in 1980; it is assumed that on this occasion another restoration took place.
The present restoration saw the frescoes again detached from the wall. This could be done only after the anchoring screws that held them in place were removed from the outer edges of the wall. The frescoes were then brought to the transept of the church, where a table was installed and the subsequent restoration carried out. The fibreglass supports on which the frescoes are mounted were found to be in good condition. Since they continue to be suitable for the paintings’ long-lasting preservation, they were kept in place.
The cleaning was carried out using reactive packs of ammonium carbonate diluted 10% in H2O and kept in contact with the painted surfaces for a short time: this operation made it possible to remove the old repaints in the background and the numerous surface retouches. The finishes delicately painted a secco were protected with acrylic resin and dabbed with distilled water. Numerous areas of discoloured grout were removed and replaced with a mortar made from slaked lime, marble dust, travertine dust and sieved river sand with a minimum addition of acrylic resin. The final reintegration with watercolour restored the colours to their original tones. Areas now permanently lost were filled with the "hatching" method. Abraded areas were treated with tone-reducing glazes. After carefully checking the stability wall support, the old plastic dowels were replaced with new dowels of the same diameter in order to be able to subsequently fix the supports using brass screws, some of which had been replaced. The crack in the wall corresponding to the perimeter of the previous detachment was sealed with a neutral mortar equal to the area circumscribing both figures.
Once detached, it was clear that the frescoes did not show any signs of deterioration. They are well bonded to the fibreglass support, except for some small detachments around the edges, which were stabilized with microinjections of acrylic resin.
The main problem was the deterioration and alteration of the old retouches which, together with the presence of surface dirt, altered the chromatic reading of the work. The altered layers were removed with demineralised water and an ammonium carbonate solution applied with a brush. In some parts it was necessary to remove traces of resin from the surface. These were probably residues of the fixatives applied during the previous detachment; a special solvent (acetone) was applied.
Inconsistent fillings, made with unsuitable materials, were removed and replaced with lime and sand mortar. Retouching was carried out with watercolour paints with the aim of recreating as complete and harmonious a reading as possible. All the neutral fillings in the parts lost during the addition of the marble altar and the later detachment operations were completely removed as they were done in outdated methods. The losses were filled smoother with a mortar made from slaked gravel, sand and acrylic resin, which provided a more harmonious tone to the whole.
During the first phases of work, tests were carried out underneath the plasterwork of the dome to find if Stagi’s 18th-century decorations were intact. After conducting the appropriate tests, it was found that a large part of Stagi’s work was recoverable. The whitewash was removed with alcohol and then with a scalpel. When the restoration was completed, the missing areas integrated with watercolour.
The colours and underlying preparation did not present any problems except for some slight lifting. Micro-injections of acrylic resins were used to remedy the lifting. Restorations over time have partly compromised some of the colours in the dome, which were originally brighter.
Cleaning was carried out with the help of waxy emulsions and ketone solvents; calibrating the contact times by means of light massaging with soft brushes, we gradually remove yellowed varnishes and old retouches.
In the Annunciation, the preparatory drawing was transferred onto the fresh plaster by means of a cartoon (the rounded marks of the tracing tool used are still visible). The cartoon followed the wall’s design and respected its measurements. A precious preparatory drawing of the angel, sketched in red chalk and watercolour, is today at the Uffizi along with other preparatory drawings for the chapel.
The fresco is made up of seventeen giornate, or individual plaster layers: there are eight giornate for the angel and nine for the Virgin. The sequence in which the giornate were painted is not certain, nor is the amount of time it took Pontormo to paint them. Certainly, however, the central window and its pietra serena frame dictated the design of the subsequent bands of overlapping plaster, painted with similar geometric designs. Some direct engravings were found on the designs around window’s, on the painted grey corbels and on the Virgin’s lectern.
As a result of its post-flood detachment and the destruction of plaster that originally outlined the architectural elements, it is not possible to establish the precise order in which the frescoes were painted. Pontormo’s colors are mainly based on iron oxides and vary from yellow or burnt ochres to intense reds, with the probable use of enamel for the blue of the Madonna's robe and malachite mixed with bianco di San Giovanni (a lime white pigment common in the period), alternating with violet to highlight the iridescent two-tone of the veil.
The colours partly resemble those of the Deposition. They are characterized by a light that fills inside the Virgin’s house, which seems to be a Florentine palazzo, its vaulted, lime-stained ceiling supported by corbels of pietra serena. White lead and mineral colours (minium and vermilion), pure or mixed, are used for a secco finishes on the angel's wings and on the part of the lips of the angel and the Virgin. Once again, shadows are reduced to a minimum. Other colours are mixed with white lime. The work seems illuminated regardless of the source of the light, creating singular effects on the wall and panel. The complexions are painted in shades of pink, in bianco di San Giovanni and red ochre, while the curls of the hair are made in yellow ochre and red ochre, lightened with bianco di San Giovanni or darkened with carbon black. Pontormo used different brushes, from very large to very small. As in the Deposition, he outlined areas in shadow. He blurred the clothing of both figures, using some sharper brushstrokes to highlight anatomical details such as hands and feet.
The dome was originally painted by Pontormo and depicted God the Father surrounded by four church patriarchs. During the construction of the viewing gallery 1766, the dome was almost completely demolished. During restoration, however, it was discovered that as much as 40 cm of the original dome had been preserved. This original dome had been built by Brunelleschi in the second decade of the 15th century in herringbone brick. The new, 18th-century dome was built using baked bricks, which were placed in a 'knife' pattern, simply placed against the original base and then developed with a lowered arch section. Domenico Stagi added a new plaster layer over these bricks to paint the false dome and lantern, decorated with lacunars and circular medallions with heads of winged putti.
At the beginning of the restoration work, preliminary tests revealed fragments of Stagi’s painting. It was therefore decided, in agreement with the Works Management, to proceed with removing the whitewash and bring Stagi's work, previously known only from documents, back to light.
Only a few colours were used in Stagi’s fresco: lime white, carbon black, enamel blue and yellow ochre. The technique is typical of the 18th century; instead of the giornate used in Pontormo’s time, Stagi used granular plaster and mineral colours mixed with white of lime. It has not been possible to determine when Stagi’s frescoes were whitewashed. Some of the plaster was missing, having apparently been demolished in the last century when electrical wiring was added.
Cleaning was performed with alcohol and water to remove the paint. A scalpel was used to remove the layers of whitewash. Gaps were filled with mortars based in slaked lime and sieved river sands, and the reintegration was executed in tempera and watercolour paints, which was applied for successive glazes.