Conserving Polychrome Surfaces in the Church of Nossa Senhora da Conceição dos Militares in Recife, Brazil

Introduction

The Church of Nossa Senhora da Conceição dos Militares in the historic center of Recife, a city in the northeastern Brazilian state of Pernambuco, was built and decorated in the eighteenth century during the Portuguese colonial period (see figs. 1–2).^[1] A Baroque monument protected by the Brazilian government, it is rich in architecturally integrated decorative elements, including gilded and polychrome carving, painted panels, and polychrome stonework. The building underwent several interventions over the course of its history, including, starting in the nineteenth century, the application of successive layers of white overpaint. Such overpaint is a significant problem in most polychromed surfaces of Baroque religious buildings and a major factor in contemporary misunderstandings of their aesthetic and historic character. Studying the conservation intervention conducted from 2017 to 2021, which removed the overpaint and revealed the original polychromed surfaces hidden beneath, therefore, affords insights relevant to the conservation of other Baroque interiors.1

In this essay, we offer just such an examination, recounting the concept and methodology employed in this intervention and offering a theoretical reflection on the discovery, characterization, classification, and (re)presentation of colors in the Baroque interior of Conceição dos Militares.^[2] The approach undertaken considered the work as a “whole object”—that is, monument and integrated decorative elements—not just the architectural surfaces.^[3] Throughout we emphasize how we recorded and documented the original colors of the Baroque interior with the greatest possible rigor, using a standardized color system that will facilitate both comparison with other interiors and better control and monitoring of color changes within Conceição dos Militares in the future.2

Conceição dos Militares’s Construction and History

Construction of Conceição dos Militares began around 1723–24 with the chancel. The wood carving that covers the interior of the church was completed in 1757. It consists of three altarpieces, two pulpits, eight tribunes, and the total covering of the crossing arch, which establishes a connection with the carving of the main altarpiece, which was produced earlier, possibly in the mid-1740s.^[4] It is likely that the complete interior decoration of the church was finished in the 1780s, although the lack of documentation from the time makes it impossible to know with certainty. In this period, more precisely in 1781, a representation of the First Battle of Guararapes (part of the conflict between Dutch and Portuguese forces for control of this region) was painted on the ceiling of the narthex. The imagery of this painting associated Our Lady of Conception with the belief in Marian protection of the Luso-Brazilian military.3

Brazil witnessed a great flourishing of religious art in the eighteenth century, particularly in the Baroque and Rococo styles.^[5] Several churches blended the two styles or, as in the case of Conceição dos Militares, are configured in the Baroque style but display features characteristic of the transition to the Rococo. This particular church stands out for the richness, detail, and extent of its art and ornamentation, visible, for example, in its ceiling, which art historians Ribeiro and Ribeiro have described as bearing “exuberant wood carved decoration involving pictorial panels, already signaling the transition to Rococo, with the use of striated and wavy Tridacna shells” (fig. 3).^[6]4

The absence of eighteenth-century documentation prevents us from reconstructing the history of the church in detail; archival research did not discover any minutes or revenue and expense books from the eighteenth century, making it impossible for us to follow the evolution of the construction or to identify the artists and craftsmen who produced the decorative and artistic elements inside the church.5

However, we do know that, starting at the end of the nineteenth century, the church underwent several interventions that involved covering the interior with successive layers of white paint. Other buildings in the historic center of Recife, such as the Church of São José do Ribamar and the Mother Church of Santo Antônio, were painted in this way as well, as were Baroque religious monuments elsewhere in the country, making it clear that a new aesthetic—Neoclassicism—was rising in popularity. Neoclassicism, a complex movement that began in Europe in the 1750s, aimed to revive elements of ancient Greek and Roman art and architecture.^[7] According to architect José Aguiar, in practice, this meant that a pragmatic aesthetic replaced those previous, more decorative ones: “The ‘functionalist’ white color floods the interiors of buildings.”^[8] This tendency to repaint in white obscured the original color schemes, and has offered paint historians many opportunities to study nineteenth-century materials and their composition and conservators with many occasions for improving processes for removing overlapping layers of paint.6

The Quest for Baroque Color and the Necessity of Collaboration

Current conservation interventions on religious buildings in Brazil and South America more broadly tend to focus on recovering the original Baroque polychromed surfaces; examples in Brazil include the Mother Church of Nossa Senhora Divina Pastora, in Sergipe; the Mother Church of Nossa Senhora da Conceição, in Conceição do Mato Dentro, Minas Gerais; and the Church of Nossa Senhora da Candelária, in Itu, São Paulo.^[9] These interventions revealed unknown historical layers that, in nearly all cases, change our understanding of these churches’ interiors and have contributed significantly to the economic development of the areas around the structures, especially through religious and cultural tourism.7

The interiors of Baroque churches in Brazil are characterized by the harmonious interaction of the decorative elements and the architecture, and color plays an important role in highlighting the aesthetic features of these spaces. However, conservation interventions to recover the interiors’ polychromies are usually performed in a fragmented and disconnected manner with, for example, structural intervention carried out before the integrated decorative elements are restored (and carried out without sufficient consideration of them), resulting in unsatisfactory outcomes. What is lacking is a holistic view.8

Initially, the story of Conceição dos Militares’s conservation was no exception. Conservation of the integrated decorative elements began in 2017, after an engineering and architecture company completed its intervention on the structural aspects. During this structural work, the company treated the architectural surfaces without investigating the colors; for example, they did not carry out surveys to identify the underlying layers of paint. The conservation team’s surveys revealed the original polychromies that had been covered by successive layers of overpaint and, furthermore, that the colors of these decorative surfaces were in dialogue with those of the architectural surfaces (see figs. 4–5). The lack of communication between the engineering company and the conservation team also had ramifications for the treatment of the church’s roof. To address water leakage, the company closed the skylights that provided zenithal light to the entire main chapel, which darkened the space and altered its apparent colors. As we will see, reinstating this natural lighting by reopening the skylights was essential to restoring the original conditions of perception—and thus, the original colors—in the interior space and revealing it as an integrated whole. In sum, the disconnect between the structural and decorative interventions compromised the aesthetic of the building as a whole and also increased the overall cost of the project, as the work done by the engineering company had to be removed and redone.9

With a firm belief in the importance of study and in-depth and multidisciplinary analysis, in the rest of the paper we use our work on Conceição dos Militares as a case study to argue in favor of a methodology for conservation intervention that embraces historical buildings as wholes, integrates the structures and their decorative elements, and, particularly in the case of Baroque churches, aims to recover the original interior colors and their interaction.10

A Note on Our Conservation Methodology

The conservation team carried out a series of preliminary studies before intervening in the pictorial layers. These activities included documentation, condition assessment, and historical and iconographic studies, among others (the team had previously treated, disinfested, and consolidated the wooden supports of the pictorial decorations). Next, we began to investigate the materials and methods used in the pictorial polychromy on the interior surfaces of the church. For this purpose, we adopted the “Investigation-Action” approach of education researcher David Tripp, which combines theory and practice, aligning with our working perspective.^[10] Practical methods based on a comprehensive understanding of restoration activity from a holistic and interdisciplinary nature were added to the theoretical perspective, embracing historic buildings as a whole, integrating structures and their decorative elements, following the guidance of art historian Paul Philippot and painting conservators Paolo and Laura Mora. These methods view the work as an ensemble of interdependent and inseparable elements, with a critical scientific approach, founded on dialogue and engagement with a variety of stakeholders.^[11] For chromatic analysis, we used the methodology developed by João Pernão from the University of Lisbon, which employs the NCS (Natural Color System) for analysis, providing clear conclusions based on the three dimensions of color: hue, value, and chroma. This system is universal and easy to understand.^[12]11

The Discovery of the Colors

The company Grifo (where Pérside Omena Ribeiro is CEO and Technical Director) conducted the initial stratigraphic surveys in the chancel in 2004. Grifo also conducted a survey of the decorative elements of the nave in 2007 when the chancel restoration was underway. From 2017 to 2021, restoration took place on all the decorative/artistic elements in the nave and on the painted ceiling of the church. During this period, we also carried out a stratigraphic survey on the walls, doors, and frames, to recover the colors of the architectural surfaces throughout the interior of the church.12

The stratigraphic survey consisted of stripping the successive layers of paint on the surfaces of the various decorative/artistic elements and on the architectural surfaces. As is standard practice, this was done by creating windows, or openings, that expose either a certain layer of painting or the sequence of various layers until reaching the oldest existing paint layer (see fig. 6). The windows were made mechanically, with the aid of surgical scalpels, and without the use of chemical processes.13

We observed that despite the differences in time periods during which the carving was executed, as evident in historical research, the polychromed wooden carving in both the chancel and the nave was originally decorated to imitate stone, in shades of blue on a cream background and, less frequently, in shades of red on a cream background. The embossed ornaments and friezes were gilded, with some points highlighted with wine-colored lacquer. Research also indicated that the paint layer of the original integrated woodwork decoration in the nave—the side altarpieces, crossing arch, eight tribunes, two pulpits, and choir railing—had been sanded in several areas for the application of white paint in the nineteenth century, and thus presented many gaps in the original color.14

The Characterization of Colors

Once the pictorial layers were revealed, we performed a series of physical-chemical examinations and analyses to identify the layers’ materials and techniques, as well as the transformations they underwent, and to chemically characterize the strata that made up these layers.^[13] We collected samples and embedded parts of them in cold-polymerized acrylic resin, then cut and polished them to produce the cross-sections for identifying and visualizing the strata, initially by optical microscopy and subsequently by scanning electron microscopy. After we gathered this data, we compared it with the information obtained from the historical research to arrive at a conclusive result for this stage.15

One example is a cross-section of sample 4 (see fig. 7), collected from the frame of one of the ceiling panels, made of gilded and polychromed wood carving. The cross-section allowed us to determine that if we removed upper layers we would expose original polychromy. The sample is composed of six strata. The first two layers comprise the ground on which the original pictorial layer was applied. Layer 1 shows the ground layer with lines of calcium (Ca) and Sulfur (S), indicating a base of calcium sulfate. Above this, layer 2 shows Armenian bole (clay used in preparation for gold leaf application, applied to the carving of Conceição dos Militares, not only in the gilded area but also in polychromed areas). Layer 3, presumably the original painting from the eighteenth century, shows, at the analyzed point, the background color of the imitation stone decoration: cream (yellowish), with a lead white base (see fig. 8 and tables in the Appendix).16

In the nineteenth century, possibly between 1869 and 1870, in a major intervention identified during the historical research, the elements of the church received the first layer of overpaint, layer 4, a very irregularly thick layer containing lead white. The second layer of overpaint, layer 5, a bluish-white based on zinc oxide, was probably applied at the end of the 1930s, as indicated by a date written in graphite on the previous layer that was discovered during the removal of the paint layers. In the third and last layer of overpaint, layer 6, we identified titanium white-based paint that was probably applied between 1968 and 1970 by the Secretaria do Patrimônio Histórico e Artístico Nacional. These results can be observed in the X-ray fluorescence spectra. The binder of this last layer was identified as alkyd resin, through analysis by pyrolysis-gas chromatography, coupled to mass spectrometry. The authors are grateful to the Science Department at the Getty Conservation Institute for the analytical results concerning the chemical composition of the alkyd paint layer, identified as a component of the overpaint on layer 6 (see fig. 7a).17

Other samples allowed for identification of the pigments found in the imitation stone decoration of the polychrome carving, on the cream background color (layer 3) (see the samples in figs. 9–10).^[14] The stone imitation in shades of blue, identified in sample 3, collected on the right side of the chancel, provide evidence of the presence of blue verditer and indigo (see fig. 9). The stone imitation in shades of red (sample 3677T), collected on the table of the right-side altarpiece, show the presence of vermilion, red lead, and lead white (see fig. 10).18

The wood carved decoration was completed with gilding, present in the reliefs of the ornaments and friezes, and with finishing glazes on the surfaces that provide lighter and darker tones accentuating the depth in the bas-reliefs. There are also red glazes applied over silvering. It is worth emphasizing how rare it is to find wine-red glazes applied over silvering, which appears in Conceição dos Militares on the curtains of the altarpieces and the lambrequins of the valances. These glazes are composed of a resinous medium consisting of terpene resins, starch grains, and a red dye, which could be madder, brazilwood, or another red dye available at the time (see figs. 11–12).^[15] Luiz Souza identified this type of rare red glaze in Brazil for the first time in his investigation of the evolution of polychrome technology in sculptures in Minas Gerais from the eighteenth century.^[16] He is undertaking further studies following the red glaze’s description and production recipe per the Bologna Manuscript.^[17]19

After characterizing the pictorial layers, we measured and classified the colors using the Natural Color System (NCS), specifically the NCS 1950 palette, which has 1,950 cataloged colors, associated with the colorimeter equipment, Colourpin SE® and Color Scan 2.0 RM 200 models from the NCS® brand.^[18] The surface color can be read by a colorimeter, without the interference of human perception or external lighting conditions. This made it possible to evaluate and classify color samples in many elements of the interior—the carving, stonework, architectural surfaces, and panels—according to their luminosity (the relationship between the black and white parts that make up the color mix), chromaticity (the relationship of color intensity and vibrancy), and hue (attribute of color that distinguishes different pure colors from one another on the color wheel), as shown in table 1. The readings were taken at different points in the conservation intervention, first during the discovery of the polychromy and then during the removal of overpaint layers. The colorimeter was positioned on the surfaces of the elements, avoiding, as much as possible, the direct incidence of light on the device.20

It is generally agreed that the appearance and even the material composition of painted surfaces start to change almost as soon as they are applied due to various factors, including the drying process; the eventual curing of the binding media; and oxidation and yellowing of varnishes, glazes, and pigments, induced by chemical contamination in the environment or by light, or both. There may also be changes, particularly in church ceilings and altars, because of roof leaks, especially when coupled with partial dissolution of some of the paint layers’ inorganic components, such as lead white, which may cause pH changes in the medium. For example, brown patterns may form in Prussian blue due to chemical changes in an alkaline medium. In addition, colored surfaces may be altered by deposition of dust and contaminants such as the products of the combustion of candles. In some situations, even the process of removing overpaint may affect the appearance of the original surface layer because of the chemicals or physical agents used in the removal. Acknowledging that the painted surfaces may indeed have changed over time, the color measurement we performed on all of the decoration in an interior allowed us to perceive the original color scheme of the church as a whole. Color measurement also establishes a “control” or reference set of measurements that may be used in the future to identify color changes that may occur with the passage of time.21

The Wood Carving

Our measurement and classification of colors began with the polychromed and gilded wood carving throughout the interior of the church. We observed a chromatic harmony between colors, even when they differed in tonality or luminosity. For instance, the dark blue and green tones of the stone imitation show, for the most part, an abundance of black in their mixtures. There are areas with brighter tones consisting of a deep blue with less black, as in color NCS S 6010-R90B (3a). Although we found both darker and brighter blue tonalities, the brighter blues seem to be darker due to the contrast with adjacent colors. Similarly, despite the variety of shades present in the space, the subtle variations in the shade, tone, or saturation of a specific color give the impression of analogous colors. The background of the wood carving’s composition is a cream color found to contain a predominance of Y20R hue—that is, yellow with 20 percent red (1c, 2c, 4c). There were, however, variations with more red, with hue Y30R, with 30 percent red (5c), being the most common of these.22

A diagram of these samples makes clear the multiplicity of hues in the composition. They range from red to green, with analogous colors in proximity to one another. Colors of similar brightness are also in proximity to one another, as the color nuance triangle shows. There are very few colors with percentages of chromaticity between 0 and 20 percent (fig. 13).23

In the polychromy of the wood carving elements there are also red tones in the stone imitation on the tables of the retables and the bases of the crossing arch (items 6 and 7 in table 1). A burgundy color, produced by lacquer applied on silver surfaces, appears on the curtains at the top of the altarpieces and on the lambrequins on the tribunes and pulpits. The nuances show variety, especially due to the reflection of the metallic surface under the lacquer. In samples NCS S 8010-Y50R (9a) and NCS S 8010-Y90R (9b) the black index is 80 percent and the chromaticity is 10 percent.24

The gilding present in the ornaments and friezes also presents a wide variety of surface colors. The color samples presented in item 8 in table 1 served as a reference for reintegrating the gilding gaps in the extant gilded surfaces.25

The Painted Stone

We next performed color readings on the stonework elements, which present polychrome shades of blue and red and golden friezes. And, as in the other polychrome areas, they have variations in shades, observed in the readings (see table 2).26

The Architectural Surfaces

We also carried out color classification and analysis on the architectural surfaces, where we confirmed that the original colors of these areas are part of the chromatic composition of the ensemble (see table 3). Stratigraphic surveys performed in different areas of the church’s internal wall showed the existence of colored mortar below the white overpaint layers. The chromatic reading, carried out on the open windows in the stratigraphic prospections, revealed the predominance of a cream color similar to the background colors of the decorative elements, with a variety of colors similar to the variety in the other surfaces. In the samples presented, there are nuances with a low incidence of black (5 percent), and a chromaticity of equal value in the color NCS S 0505-Y30R (12a). Color NCS S 0907-Y30R (12b) preserves the same color hue (Y30R), but with a slight difference in the percentage of black in the mixture (9 percent), and a chromaticity of 7 percent, resulting in a little less brightness. There is a remarkable predominance of yellow hue with 30 percent of red in the observed samples (Y30R).27

Traces of color found in the area of the hardware of the doors and windows were original and of a dark green hue. These elements were covered by a bluish-gray surface layer, applied during a recent intervention by the engineering company before the restoration of the decorative elements in the church. The disparity between the colors is notable, with the original color NCS S 7010-B70G (13b) having a luminosity of 70 percent black and a chromaticity of 10 percent, while the most recent paint layer presented the color NCS S 3005-R80B(13a), with a luminosity of 30 percent black and a chromaticity of 5 percent, and is, therefore, much more luminous. They originate from different hues, the original color being blue with 70 percent green, while the recent one is red with 80 percent blue.28

The columns of the narthex, under layers of overpaint, bore a beautiful stone imitation, with red background tones, cream-colored veins, and gray spots. All measurements carried out revealed yellow tones with levels close to red, varying according to the percentage of black and the chromaticity.29

The classification of colors of the carved wood, painted stones, and architectural surfaces represent only some of the readings carried out inside the church. However, they make evident the scheme of the original chromatic composition with abundant colors creating a harmonious, integrated ensemble. A three-dimensional model shows the arrangement of colors and their proximity to each other, with a wide variety of hues covering the analyzed surfaces (fig. 14).30

The Panel Paintings: The Baptism of Christ by Saint John the Baptist and The Battle of Guararapes

We measured and classified the colors in these works before and after the restoration intervention, using the same methodology as for the polychrome carving. As examples, we discuss here The Baptism of Christ by Saint John the Baptist, located on the wall of the crossing, where we recovered the eighteenth-century painting that was covered by the nineteenth-century one, and a detail of The Battle of Guararapes (1781), located in the subchoir lining, on which we performed varnish removal.31

Figure 15 shows the eighteenth- and nineteenth-century compositions of The Baptism of Christ by Saint John the Baptist. The nineteenth-century composition is on the left, and the original, underlying painting from the eighteenth century is on the right. Some of the shades in the nineteenth-century painting were close to shades in the original eighteenth-century composition, but many more were different. To take one example, color NCS S 6010-Y30R from the original, eighteenth-century painting (point 47 in fig. 15), a yellow with a red approximation of 30 percent, was covered by color NCS S 4502-G, a pure green with 45 percent luminosity, constituting a lighter color with a different hue. Overall, the two palettes differ markedly, with the nineteenth-century one consisting of lighter tones, and the eighteenth-century one consisting of darker tones, as can be seen in point 48 in fig. 15.32

If we isolate the tonalities in both paintings, we obtain a simplified palette that permits side-by-side comparison of the main tones (see fig. 16). This reveals the presence of yellowish and warm tones in the nineteenth-century painting, and, by contrast, tones that are closer to red, with a tendency toward less bright tones, in the eighteenth-century painting. There is also a greater variety of greens in the nineteenth-century painting, as well as less black in the mixtures of colors and more accentuated nuances. In the palette of the original painting, there is a higher percentage of black in the mixtures, and generally colder tones.33

The colors of The Battle of Guararapes were completely altered by the darkening of the varnish. To analyze these chromatic alterations, we carried out readings before and after the varnish removal, at the same points. There is noticeable variation in the colors after the varnish removal; in some cases, varnish removal is the key to understanding the color underneath (see fig. 17). In the detail of the painting with the varnish still in place, there is a predominance of colors closer to yellow, and even the pure hue of the color (point 51, color NCS S 6020-Y). In the detail of the painting after the varnish was removed, the colors are closer to green and even blue. Point 54, for instance, constituted a dark green close to yellow (NCS S 8010-G70Y) before varnish removal that, after removal, appears as a blue (NCS S 7010-B90G). Similar color modifications are perceptible in several other points, in different areas. Generally speaking, the unvarnished paint presents a greater variety of nuances of hues and has less accentuated chromaticity, between 2 and 30 percent. The varnished colors, in addition to containing a higher percentage of black in their mixtures (up to 85 percent), have a higher chromaticity, reaching 40 percent in some points. Consequently, the varnished palette presents nuances with a higher percentage of black and more apparent chromaticity, while the palette after the varnish removal presents slightly brighter, more nuanced colors, with more greens and blues present, in addition to a smoother chromaticity. This change in colors due to varnish is common and calls to mind the statement of Michel-Eugène Chevreul, the eighteenth-century French chemist and color researcher, about a certain type of color harmony, when we observe some colors as if we were seeing them “through a slightly stained glass window.”^[19]34

In conclusion, we contend that the method of color categorization we performed on the wood carving, painted stone, architectural surfaces, and panel paintings may be used and developed as a tool of particular importance for surveying and documenting the polychromy of surfaces, with a focus on monitoring of change. It constitutes an innovative element in conservation-restoration work that can support identification of possible color changes and/or degradation in the future.35

A Note on (Re)presentation

In his 2002 doctoral thesis, José Aguiar, based on the thinking of Paolo and Laura Mora, enumerated the principal theoretical and practical considerations that conservators must bring to bear in every chromatic conservation project. First, conservators must seek to preserve the existing color. Second, they must consider the “prima chromia”—that is, the original image, as conceived by the craftsperson or artist. Third, they must take into account the color and characteristics of the historical environment. Finally, conservators must base the final appearance on the most aesthetic or historically significant color of the architecture—the color that characterized the building when it became historical or emblematic in the memory of a place, even when that color is far from the original concept.^[20] In our work on Conceição dos Militares, we embraced all of these principles, but with a few nuances. First, concerning the reference to a previous chroma, we want to emphasize that when old paint reemerges, it has aged over time so it will not appear as bright and shiny as a new surface. It is also important to understand, with respect to the conservation and restoration of Conceição dos Militares, the context of the decision-making process, in which the Instituto do Patrimônio Histórico e Artístico Nacional (IPHAN) made the final determinations about which surfaces should be removed or retained. Our task on the conservation team was to provide scientific results and philosophical arguments to support IPHAN’s decisions.36

Overpainting of church decoration, as well as of wooden polychrome sculptures, is a common and well-known problem around the world, not just in the Americas, but also in Africa, Asia, and Europe. Arguably, the problem is particularly acute in Brazil, where, in the nineteenth century, it was common practice, even a trend, to paint the entireties of church interiors white. Furthermore, from the 1940s through the 1980s, there was another trend, coordinated and executed by IPHAN, whereby conservators completely removed not just the overpaint but also the polychrome and gilded layers, stripping altarpieces, wood carvings, and ceilings alike down to plain wood, unfortunately and irreversibly causing the loss of the entire polychromy. By contrast, IPHAN has now adopted an approach promoting the removal of overpaint and searching for the original interior colors. We have aimed to contribute to this decision-making process by conducting scientific, historical, and art historical research that may contribute to a better understanding of the contemporary overpaint removal and presentation criteria adopted by IPHAN.37

Removal of the Overpaint

Prior to removing the overpaint, we performed solubility tests with individual solvents and combinations of them, on the surfaces of the various architectural and decorative elements. Our choice of solvents or solvent mixtures was based on the composition of each layer to be removed, the need to find a product that would remove only the targeted layer without affecting the underlying layers, and the need to avoid erosion or abrasion of the original layer or to leave product residues. In general, the practice of overpaint removal still needs more study and the development of a methodological approach, in order to adopt more ecologically friendly products or processes, with less impact on both human health and the environment. 38

Chromatic Reintegration

The conservation team observed that in the carved elements of the chancel and carved Cymatium of the roof, the polychromy had small areas of losses and lacunae due to termites and water leaks in the wooden support. But in general, these losses were relatively small, such that they did not prevent the appreciation and understanding of the decoration as a whole. However, in the nave of the church there were much more substantial losses caused by a destructive sanding of the surfaces in the nineteenth century.39

The technicians from IPHAN, the team of researchers, and the coordinator of the conservation and restoration work, Pérside Omena Ribeiro, held several discussions to decide on the criteria and techniques to be adopted for the reintegration of these areas. Agreeing that returning the space to its original aesthetics was of utmost importance for the ensemble, we carried out the chromatic reintegration of the wood carved elements, recognizing that the original polychromed layers were similar throughout the ensemble and taking an approach based on critical conservation theory.^[21] As Philippot explains, both large and small lacunae can make it difficult for viewers to read and understand an object. Accordingly, the chromatic reintegration of losses is critical to reestablishing the formal unity of the interior as a whole.^[22]40

Because the nave of Conceição dos Militares presents large losses and most of the time there exist no references for its chromatic composition, we reconstituted the polychromy by transferring the chromatic composition of the stone imitation from areas that contained the original painting in its entirety, such as the ceiling, cymatium, and other areas. Next, we used a complete reintegration with visible retouching. This means that the retouching is perceptible and distinct from the original in a way that is evident to the naked eye at close range without the need for special documentation. In this case, we applied paint using a series of small dots in colors similar to those of the original polychromy. This method of chromatic reintegration ensures that we do not give the impression that the conservation is original. If viewers get close to the pictorial surfaces, they will be able to identify the intervention, while, at a normal observation distance, they experience the exposed surfaces as a unified aesthetic whole. Art technology scholar Jilleen Nadolny refers to this practice as differentiated mimetics.^[23] We used the same method in the chromatic reintegration of the stonework elements (fig. 18).41

We recomposed losses in the gilded areas using gold leaf and, in areas not directly visible to viewers, mica-based gouache paint. (We used mica only in the recomposition of small losses of original gilding, thus minimizing changes in the surface appearance.^[24]) To reintegrate the new areas with the old gold, we applied an artificial glaze that, like the original gilding, had a yellow hue ranging from 20 and 30 percent with red (Y20R and Y30R).42

The paintings on the sixteen panels in the church—two in the chancel, eleven on the nave’s ceiling, two on the crossing wall, and one on the subchoir’s ceiling—were in good condition, with only minor losses. Therefore, we reintegrated chroma with an illusionist or mimetic technique that reintegrates the color, form, and texture in the painting in a way that is invisible to regular viewers.^[25]43

We identified the original painting of the walls as having been made by a colored lime mortar technique. After carrying out color readings (see table 3), the painting was redone using a technique and color similar to the original, as the original painting presented many losses, caused by deterioration and various prior interventions.44

The doors and windows were painted with dark green industrial paint (alkyd), in the original color, NCS S 7010-B70G, found in the prospection (see table 3). The columns in the narthex were in excellent condition and had losses only in the gilding of the capitals, which we treated using the same procedure used for the gaps in the gilding of the wood carving.45

Light and Color

It is impossible to talk about recovering the colors of a space without considering that space’s lighting. According to João Pernão, “light is the genesis of visual perception, and color is its vehicle.”^[26] We might even venture to say that color is the shape of space, through which we perceive the limits and shapes of the environment around us. Thus, at Conceição dos Militares, we made a point of studying the light conditions inside the church, both natural and artificial. Natural lighting was already a concern in the eighteenth century, as evidenced by a meeting of the Brotherhood of Nossa Senhora da Conceição dos Militares in 1754, when it was decided to raise the ceiling of the church to open new windows for the entry of natural light. As already mentioned, prior to the intervention in 2017, there was a previous one on the church ceiling, carried out by an engineering and architectural company, which closed the skylights that provided zenithal light to the chancel through two oculi. To reinstate this natural lighting as initially designed in the monument’s construction plan (see fig. 19), we reopened the skylights and documented the light in the environment before and after doing so, through photographs taken at different times of the day. This measure played a crucial role in restoring the original conditions for the perception and presentation of the interior space as a fully integrated whole.46

Color Mapping for Monitoring Change

At Conceição dos Militares, we mapped the colors on the surfaces of the integrated decorative and artistic elements and on the architectural surfaces by measuring and classifying them with a universal coded system, the Natural Color System (NCS), as described above. We hope that this essay makes a compelling case that the method we employed would be effective in other, similar restoration campaigns, and, more broadly, that proper monitoring and characterization of both old and new surfaces is important.47

With respect to the latter point, the case of Conceição dos Militares attests to the importance of mapping colors. The polychromies we exposed in the church had been, in a sense, protected by the overpaint. The factors that contributed to deterioration in the nineteenth century, when the polychromies were covered up, are different from the factors that could alter them today, which are mainly weather and pollution. Mapping the colors will permit monitoring future chromatic alterations of the painted layers, through measurements carried out on the same points we analyzed. Figure 20 offers an example of one such map, that of The Annunciation of the Archangel Gabriel to Mary, one of the ceiling panels in the church’s nave.48

Conclusions

Among the main aims of our work at Conceição dos Militares was bringing the original colors back to light in the interior of the church. To do so, we developed a holistic intervention that included integrating the various decorative/artistic and architectural elements in the space, as well as reflecting on the presence and quality of light in the space and how it shapes the perception of the ensemble. Conducting this intervention allowed us to develop a methodology that incorporates and adapts procedures from various disciplines, connecting conservation principles to architecture, aesthetics, conservation science (chemistry, color science, and physics), and history, among others, in what we view as a real heritage science perspective.49

It is also important to note that this project represents, if not the first attempt in the international literature, at least the first attempt in Brazilian studies to integrate not only the chemical and stratigraphic survey of colors but also their appearance on the surface after treatment, through reading and classification using a universal coded system. This will allow future measurements to be made on the same surfaces, thus serving as a reliable tool for monitoring chromatic changes over time.50

Our work on Conceição dos Militares made it possible to see the church interior as a whole for the first time in centuries. This recovered the physical beauty of its Baroque interior, a space that has immense symbolic, affective, and mystical meaning for the Catholic community and Recife’s residents in general. The restoration also stimulated the revitalization of the surrounding area, contributing to its economic development via religious and cultural tourism. Finally, our efforts supported cultural heritage education through guided tours that showcase the Baroque interior and historical character of the monument to visitors. The revival of Nossa Senhora da Conceição dos Militares has significance beyond its immediate surroundings: as part of the Baroque “circuit” in Recife, the church is also a national reference point and holds symbolic importance for the nation as a whole. The problem of overpaint removal in churches and architectural decorated surfaces is of common concern to several societies around the world. In this essay, we have tried to approach the problem from a methodological and conceptual perspective. There are still many gaps to be filled, such as the development of a more “green” approach to overpaint removal, as well as the definition of limits to the irresponsible and unrestricted use of mica. In terms of research and dissemination of knowledge, our studies lead clearly to the need to develop more didactic tools to understand the original finishing of gilded surfaces, including the use of colored glazes and resinous varnishes. We are honored to have been a part of this project and hope our work will inspire similar endeavors throughout Brazil.51

Banner image: Detail of fig. 3.52