Maria Carolina Peña Mariño
Easel Painting Conservator
Portrait of Friar Christopher of Torres by Gaspar de Figueroa (1643).
The idea behind this technical study was to improve on the lack of information on materials and techniques used by local painters in Colombia during the colonial period, using examination methods which are not usual in the country and taking advantage of the upcoming restoration of the portrait of Friar Christopher of Torres, the best executed portrait by the renowed17th century painter Gaspar de Figueroa.
The study entailed historical research into Gaspar de Figueroa and his workshop, the artists' materials available in America between the 16th and 18th centuries, and the provenance and history of the painting, in conjunction with a thorough observation of the surface of the painting under magnification and different investigative imaging and analytical methods of examination: Transmitted Light photograph, Raking light photograph, UV light photograph (UV), X-Radiography (XR), and Reflected and Transmitted Infrared Photography (RIR/TIR), Cross Sections and Scanning Electron Microscopy/ Energy Dispersive X-Ray (SEM-EDX).
This research project was awarded the 2020 grant for research in conservation and restoration of cultural heritage offered by the Ministry of Culture of Colombia, and hopes to be published in the 2021 Special Issue on “Practical Approaches to Technical Research” of the Journal of the American Institute of Conservation.
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Gaspar de Figueroa, Portrait of Frair Christopher of Torres, 1643, Oil on canvas, 202 x 109cm . Universidad del Rosario, Bogotá. Photography taken by Javier Humberto Jimenez ©.
Gaspar de Figueroa (c.1594- 1658), was a recognized painter in the New Kingdom of Granada (Modern day Colombia) during the 17th century. He owned a very prolific family workshop in Santafé de Bogotá, which received plenty of commissions from the Catholic Church and different religious orders. His work is mostly comprised of paintings of religious subjects (Christ, the Saints, the life of the Virgin Mary) based on European engravings, as well as portraits of donors and high dignitaries of the church. It is common to find several copies of the same attributed painting but with disparities in quality and skills. This suggests a high degree of collaboration within the workshop and difficults the tracing of his evolution as an artist. As expected, only few of his paintings are signed. The portrait of Friar Christopher of Torres, Archbishop of Santafé de Bogotá and founder of the Mayor College of Our Lady of the Rosary is one of those and is considered by local art scholars as one of his best works.
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It is not known who commissioned the painting or when exactly it was bequeathed to the Colegio Mayor (Today Universidad del Rosario). There are no references of it on Friar Torres’ will, nor in the episcopal historical archives. The painting appears for the first time in a written inventory of the assets of the College chancellor’s apartments made in 1783, and 10 years later in another iteration of the inventory. From then on, the painting’s life can be traced, and it is known that during the 19th and 20th centuries, this portrait survived earthquakes, independence battles, wartime, fires and riots. Considering all of the above, it is in relatively good condition.
Gaspar de Figueroa, Portrait of Frair Christopher of Torres, 1643, Whole back. Photography taken by Javier Humberto Jimenez ©.
1. Horizontal seam seen from the front. 2. Horizontal seam seen from the back. 3. Manual tack securing the painting to its strainer.
Support
The painting is an unlined oil on canvas with a height of 202 cm and a width of 109cm. The support is a medium weight tightly woven plain canvas, made from three pieces of linen joined together in the direction of the weft using whip-stitch seams.
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The painting’s auxiliary support is a rustic 5-member American cedar wood strainer. It exhibits mortice and tenor joints reinforced with wooden pegs and a crossbar. The painting is attached to the strainer with randomly spaced iron tacks (some reinforced later). The fact than the existing tacks corresponds to the canvas cusping suggest the strainer and mounting might be original. In addition, the perimeter of the canvas is glued to the front face of the strainer as well as the tacking margins, which reinforces this hypothesis. This was a practice that was recommended in the Spanish painting treatises and that has been previously reported in technical examinations of paintings of Latin American origin .
Preparation layers:
The preparatory system corresponds to a size coating followed by an oil ground layer. The size is a relatively even and thin layer of animal glue, identified by using Amido Black staining. Linen fibres surrounded by this layer were observed in many of the samples, which might suggest the size impregnated the canvas very effectively giving good adhesion between the support and the paint layers. Chalk, white, red, black and lake pigments and clusters of oil were also identified within this layer. This could be explained by the addition of palette scrappings or of pigments settled at the bottom of the rinsing jar, which were added to give the glue layer more flexibility and body.
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The ground layer is made of yellow ochre in oil, with variable amounts of lead white. Its application is heterogenous and uneven across the canvas, as can be clearly seen in the X-ray. The sample taken from the corner of the table demonstrates how the yellow earth ground here is almost inexistent.
X-ray composite of the Portrait of Saint Christopher of Torres. Taken by DMV Javier Sandoval©.
1. Detail of cross section #10 taken from the tunic using UV light showing the linen fibbers impregnated by a proteinaceous size (positive to amido black staining). 2. Cross section #12 taken from the drapery showing a size layer with the inclusion of pigment particles, followed by a yellow earth ground. 3. Cross section #5 taken from the tablecloth showing size layer with the inclusion of pigment particles and the absence of the yellow earth ground layer.
Cross section #13 taken from the drapery showing dark pigment particles on top of the yellow earth ground layer.
Detail of the face of the sitter in transmitted infrared photography. Notice the dark strokes at the right of the face that suggest the repositioning of this element.
Digital overlay of the face pattern of Friar Christopher of Torres over the 17th century anonymous portrait of this character in Bogotá's Cathedral.
X-radiography revealed a change in the location of the sitter´s ear.
Compositional planning and underdrawing
IR photography didn't show evidence of an underdrawing. This might be due to the low penetration of this technique in comparison with IR Reflectography, but it could also be because of the presence of a coloured ground or to the use of a non carbon containing material for this purpose. In a sample taken from the drapery, brown particles, possibly earths or spalt, are visible on top of the ground which might correspond to an underdrawing.
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The use of transmitted IR photography showed the defined contours of the figures and carbon rich strokes at the right of the face which suggests a total repositioning of the sitter’s head. This points to the use of a pattern of the face of the sitter in the construction of the image, feature that has been seen in other paintings by the artist.
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Digital layering of this portrait by Gaspar de Figueroa and of a 17th century version in Bogotá's Cathedral, showed an accurate alignment of the faces which indicates than the same pattern was used for both images.
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Overall, the painting exhibits minor changes to the composition. Just a few pentimenti were visible in the X-ray, which were associated with the reposition of the sitter's ear and hood. Also, reflected IR photography showed the enlargement of the left thumb, the use of pencil lines to aid in the writing of the inscription on the book and a reduction of the Virgin Mary's mantle.
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Paint layers:
The binding media is probably linseed oil, since it was the most commonly imported material to American colonies from Spain.
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The pigment palette is limited and comprised mostly of very high-quality red, yellow, brown and blue (vivianite) earth pigments which were likely locally sourced. Lead white, vermillion, two different red lake pigments (possibly a scale insect type and madder), carbon black and bone black where also identified. This is consistent with materials available to artists in 17th century America.
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Vivianite ((Fe2+)3(PO4)2·8H2O), mixed with lead white, was identified in a sample taken from the virgin's blue mantle using SEM-EDX. It was used as an underlayer for the more expensive, scarce and transparent pigment azurite. Vivianite has never been reported in paintings produced in the New Kingdom of Granada. However, there are references to its use by the Italian painter Angelino Medoro in the viceroyalty of Peru (Bruquetas Galán R. , 2009; Bruquetas Galán, et al., 2011).
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Red lakes were used extensively in this painting despite its high cost, which highlights the importance of the sitter. These organic pigments were used for glazing the red robe of the friar and the burgundy drapery. No analysis for the identification of organic substances where performed as part of this project but based on appearance, permanence, UV florescence and availability, it could be suggested that cochineal and Madder might have been used in these passages. SEM-EDX analysis pointed-out that both red lake pigments were precipitated in a calcium rich substrate and were skilfully tempered using lead oil.
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Cross-section #2 taken from the virgins mantle subject to SEM-EDX analysis. Backscatter Electron Image, optical microscopy dark field, elemental maps for Fe-K, Pb-L, Cu-K, P-K, and spot-spectrum of specific particles. Notice how the translucent blue particles are rich in Iron and Phosphorous, while the greenish blue samples at the top are rich in Copper.
Cross-section #7 taken from the Friar's robe subject to SEM-EDX analysis. Backscatter Electron Image, optical microscopy dark field, elemental maps for Pb-L, Cu-K, Al-K, Fe-K, and spot-spectrum of specific particles. Notice how the red lake glaze is rich in Calcium and Lead.
There is a generalized underpainting on top of the ground through which the artist defined the shapes and colour values within the composition. This layer is made of a mixture of yellow earths, lead white and carbon black. The amount of each pigment added to the mixture vary in relation to the lights and shadows.
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On the upper layers, different areas of the composition were blocked-in and modelled wet-on wet using opaque mid-tones colours, shades, and tints. The artist then proceeded with the application of the highlights using scumbling or by the application of fluid paint through fine and short brushstrokes. He also glazed over different areas to get the desired colour hue, increase the saturation and provide a sense of depth. Finally, he rendered all the fine details with loose but precise brushstrokes, such as in the sitter’s prayer beads, virgin and child, rings, book letters, the inscription at the top, the damask pattern, etc.
Detail of the picture of the virgin Mary
Macrophotography at 25x showing the child's hand.
Macrophotography at 25x showing the loose but precise brushstrokes on the rosary beads.
Detail of Gaspar de Figueroa's signature later reinforced in lead white paint.
Macrophotograph showing the original signature in black paint underneath.
Signature of Gaspar de Figueroa taken from his will.
The technical study of the painting revealed the signature was later reinforced with lead white paint. At close up is still possible to see the artist's original signature underneath made in black paint, which matches the signature of the artist in other paintings and in historical documents.