AIC's 53rd Annual Meeting

The Museum of Fine Arts, Boston (MFA) has one of the largest and most important collections of Japanese Buddhist sculpture outside of Japan. For five years (2019-2024), the Conservation in Action: Japanese Buddhist Sculpture in a New Light project focused on the examination and treatment of seven large-scale wooden sculptures from the Heian period (9th-12th centuries). Since 1909, a selection of Buddhist sculptures have been displayed in the Temple Room, a gallery designed to evoke the contemplative atmosphere of a Buddhist temple. During the recent project, conservators worked thousands of hours to examine, document, analyze, and stabilize the seven Temple Room sculptures, uncovering new and exciting discoveries and generating many new technical images.

Although the Temple Room aspires to place the sculptures in an “appropriate” context for viewers, it does not attempt to replicate a complete temple environment. One of the MFA’s goals was to embrace the space’s meditative ambiance by keeping it free of text panels and object placards when the Temple Room was reinstalled. A conservator was invited to join an interdepartmental group with representatives from the curatorial, interpretation, and exhibition media departments to envision what other methods might be employed to better provide contextual information and encourage close-looking of these specific seven Buddhist sculptures. The so-named Temple Room Didactic group partnered with outside collaborator Ideum, a technology company with expertise in creating museum interactives. For a year, the group worked to refine the content of an interactive didactic that was to be placed right outside the central entrance to the Temple Room.

Ideum was responsible for building a custom app that would meet the Museum’s interpretative goals and could technically support the different types of data that were slated for inclusion. For example, an opening choreographed sequence shows visitors what one might experience walking into a Buddhist temple complex in Japan and the main landing page displays 3D models of all seven sculptures in a virtual temple environment. The completed didactic encourages self-led exploration as visitors can choose a specific sculpture or opt to read about the sculptures’ fabrication. The 3D models can be rotated and are tagged with hotspots that prompt viewers to engage with additional information. In-depth conservation stories are available for three of the sculptures. The didactic includes much more information than can be shared on wall labels and gives visitors a more interactive and exploratory experience.

The Temple Room didactic project underwent several iterations as the group sorted through five years of technical data and images to select content that fit within the didactic framework and was illustrative of the interpretative narrative. The separation of complicated technical stories into short clips that fit within the navigation of a yet-unbuilt app was challenging as it was difficult to envision how the completed interactive would function. The final realized interactive didactic successfully presents conservation-derived information in a digestible manner that reinforces the reverence of these Buddhist devotional figures while highlighting the recent conservation efforts.

Since joining the Canadian Conservation Institute, many of my collaborations have taken shape during hallway conversations. When asked the simple question "How do you feel?," I responded off-topic, due to my struggles as a francophone to understand English and my preoccupation with the treatment of a mismatched veneer repair on an 19th century English piano: "I want to fill with wood, but I have several issues..."

The conservation of wooden furniture and objects often requires the integration of new components due to degradation, breakage, or loss. This process becomes particularly complex when filling large areas with an alternate material. Wood is typically the compensation material of choice, but several factors can complicate the filling process, including the availability of specific wood species and the surface characteristics of colour, grain, and finish. Importantly, there is the challenge of a colour difference developing between the object and the fill after subsequent light exposure. But what is responsible for this – the original wood, the wood fill, or both? Eric Hagan, senior conservation scientist, was kind enough to ask how I was feeling one day, and that conversation led to experiments that address this question. Using customized light ageing boxes and fadeometers, we investigated the colour change response of wood to museum lighting conditions, the influence difference light sources have, and the light dose that changes color slowly enough to be acceptable. Results from our experiments showed that all freshly sanded woods, when exposed to light without UV, undergo a rapid colour change (rated Blue Wool 1 to 3) followed by a slowdown. Experiments on mahogany and purpleheart under LED, Halogen, Fluorescent, and Ceramic Metal Halide sources seem to demonstrate that light source does not have a major influence on colour change. Initially very sensitive, all woods shift to Blue Wool 5 at approximately 50 to 60 Mlxh. 

 

Thanks to these key numbers, we concluded that wood used for a fill should be chosen based on its texture and not its colour. Moreover, an object’s original wood, depending on its age, exposure, and treatment history, may remain highly sensitive to colour change; mismatches will arise over the course of a conservator’s career, requiring re-treatment of the object. Indefinitely removing and replacing adhered wood fills is not a viable option, given the potential for damaging the object. Therefore, I had to rethink my approach to matching the colour of wood fills, which led my feet down the hallway to my colleagues in paintings conservation, Marie-Hélène Nadeau and Fiona Rutka. After testing different natural and synthetic resins, we found that Orasol dyes mixed with Aquazol 200 successfully toned the sealed, light-aged wood fill, and it was easily reversible.

Leisure Time is a largescale (320cm x 160cm) four-piece lacquer-on-wood panel painting created by Hawaiian-Vietnamese artist Tim Nguyễn in 2008.  In just 14 years, the painting exhibited unique discoloration on the surface, with bright yellows turning to dull browns, bright greens fading to dark greens, and oranges shifting to browns. While much information on Asian Lacquer exists, there is limited published research on the relationship between the materials and techniques when used as a painting medium and their degradation mechanisms. In 2023, one panel of the painting was transported from the artist’s studio in Hawaii to the Garman Art Conservation Department at SUNY Buffalo State University for research to study the materials, process of painting, and conservation possibilities.

Vietnamese lacquer, known as laccol, is derived from the sap of Toxicodendron succedaneum, a species in the Anacardiaceae family, which also includes the lacquer trees found in Japan, China, Thailand, and Burma. Lacquer is a unique substance that cures only under high humidity conditions through polymerization. While freshly made lacquer is highly durable, aged lacquer films become sensitive to light and sudden changes in humidity. Vietnamese lacquer painting, known as sơn mài, may be described as a form of reverse painting, consisting of as many as 10-20 layers. Lacquer is an art of uncertainty, as each layer can take days or even months to fully cure. By combining the lacquer with various additives, such as oils and resins, artists achieve a wide range of textures. The final image is created by carefully sanding back these layers of paint. In addition to pigments, lacquer artists use playful materials like metal leaves, mother of pearl, and shells to create depth, transparency, and intricate patterns. Traditional restoration techniques often involve using the same type of lacquer; however, these methods are irreversible and tend to age at a different rate than the original lacquer. Moreover, lacquer sap is highly toxic and can cause allergic reactions similar to those triggered by poison ivy.

The current study analyzed the materials and layer structure of the painting, via several analytical techniques. These included multimodal imaging, x-radiography, infrared reflectography, cross-sectional analysis, scanning electron microscopy with energy-dispersive X-ray spectroscopy, x-ray fluorescence spectroscopy, and Raman spectroscopy. Lacquer samples were further analyzed using THM-Py/GC-MS following Getty’s Recent Advances in Characterizing Asian Lacquer protocol. Mockup lacquer samples were custom-created, light-aged, and subjected to sea salt in an attempt to replicate the discoloration observed in the original artwork. An artist interview with Tim Nguyễn was also conducted.

The results of the research indicated that photodegradation due to light exposure combined with arsenic-containing pigments was the primary cause of the color changes in the painting. Aged samples also showed the migration of silver ions to the lacquer surface when exposed to light, where they reacted with sulfur-containing pigments forming inclusions on the lacquer surface. In examining conservation techniques, the use of traditional transparent lacquer is irreversible and unstable. It is possible that a modern synthetic varnish may be used as a coating on lacquer paintings. While more study is needed, an initial test of several conservation grade varnish formulations, including MS2A, Regalrez 1094, and Paraloid B72 was conducted and exhibited promising results.

Guqin is a Chinese plucked musical instrument with profound symbolic, aesthetic, and socio-cultural meanings. It consists of seven silk strings and a rectangular wooden soundbox painted with multi-layers of Asian lacquer-based coatings. The art of guqin has been inscribed on the UNESCO Intangible Cultural Heritage List since 2003, and the collecting of antique guqin instruments has been an important and active part of Chinese material culture since the eleventh century. Mostly resulting from natural aging processes due to playing and chemical and mechanical deteriorations of the compositional materials, craquelure appears on guqin’s surface coatings with time. Interestingly, instead of being viewed as defects or ugly, these craquelures are highly valued as cultural beauty, a sign of authenticity, and a key criterion for appraisal in the guqin collecting tradition. As the connoisseurship of guqin craquelure developed from the eleventh to the nineteenth century, various craquelure patterns were recognized, named, and associated with specific production periods.

However, these seemingly self-explanatory pattern names, such as snake-belly, ice-cracking, and plum-blossom craquelure, have never been clearly defined or illustrated in historical documents or guqin treatises. Although these terms continue to be widely used in contemporary catalogs, auctions, and museum practices, the lack of clarification and in-depth understanding of guqin craquelure patterns has caused issues like arbitrary naming, miscommunication, controversial dating and valuation, and thus puzzling the decision-making of guqin conservation treatments. 

This research used non-destructive imaging techniques, including normal and raking light photography, reflectance transformation imaging (RTI), multi-band imaging, and digital microscopy, for over fifteen historical guqin instruments in both public museums and private collections in China and the US. The goal is to document the cracking surfaces at different magnifications and lighting conditions, and segment the most characteristic visual features to re-define and distinguish those traditional pattern names. From this imaging, four comparable attributes are summarized that best differentiate the guqin craquelure patterns in planar: 1) degree of cross-linking, 2) shape and size of networked islands, 3) direction and distribution of disconnected patterns, and 4) formal features of individual cracks. Additionally, we used micro-CT to scan detached coating samples from five historical guqin to study the depth profile of the cracks and fine crackles, the stratigraphic structure of the coatings, and the distribution of the binder and filler in the ground layers. Although often disturbed by later restoration and re-lacquering layers, the micro-CT analysis proved to help study the more complex areas and distinguish craquelure patterns developing top-down that were potentially initiated by light damage, versus patterns developing bottom-up that were more likely caused by mechanical stress in between the wood substrate and the coating. 

We hope the results of this ongoing project can contribute to building a more scientific classification system of guqin craquelure and clarifying its crack-forming mechanism, which ultimately could improve current restorative and preventive conservation practices and bring more attention to the understudied category of East Asian musical instruments in the context of global collecting and cross-cultural conservation.

Russia’s invasion in February of 2022 of Ukraine dramatically altered the cultural as well as the physical landscape. Numerous Ukrainian conservators scrambled to protect their cultural heritage, while others left the country as refugees. Western conservators and conservation scientists, conservation organizations, non-profits, and foundations responded to this event with fruitful initiatives to assist in these preservation efforts and to prevent a now well-documented existential threat to Ukrainian culture. This presentation will focus on the collaborative efforts of Ukrainian conservators, conservation educators and scientists, art historians, translators, university faculty members, historic preservationists, and their peers and concerned parties outside of Ukraine. The perspective will be of an AIC Wooden Artifacts conservator, Fulbright Specialist, and Scholar to Ukraine before the war. It will illuminate the will and determination of Ukrainians to acquire and implement the conservation knowledge and values of the West under challenging circumstances.

In autumn 2022, the Balboa Art Conservation Center (BACC) received a delicate and significant object for examination: a portrait of Jassim Al-Oboudi, a prominent Iraqi actor and professor, painted on a single ply of plywood. This portrait, one of the few items the Jassim family managed to bring with them when fleeing Iraq during Saddam Hussein’s Ba’ath Party regime in the 1970s, was in a fragile state with flaking paint and numerous splits in the single ply of wood, held together as a single unit by shipping tape on the verso.

BACC paintings conservators, unfamiliar with treating a painting on a 2 mm ply, sought external advice but faced more questions and treatment options than clear solutions. The necessary research, mock-ups, and professional development needed made treatment prohibitively expensive for the family.

As a nonprofit committed to public benefit and making conservation accessible, BACC, led by Executive Director Leticia Gomez Franco, established a pro bono treatment program for objects of local cultural value that also provided opportunities for skill development for BACC conservators. Given El Cajon’s large Iraqi (Chaldean) community– the second-largest outside Iraq, after Detroit–, the portrait was an important piece of local history. Conservators Bianca Garcia and Morgan Wylder embarked on a pilot project to treat the portrait, which involved considerable additional research.

Initial consultations with conservators from various specialties revealed a lack of consensus on how to approach the treatment. Despite many ideas, practical experience with similar objects was limited. Synthesizing all recommendations, the treatment goals focused on finding a practical solution to achieve structural stability and allow the portrait to be displayed in the family’s home. Ultimately, the decision was made to return the painting to its original layered construction and back onto a plywood support. With the guidance of furniture conservators,  Morgan and Bianca learned techniques generally used to apply decorative veneers back onto wooden supports, adapting them to accommodate the paint layers. 

The project was successful on several fronts: the portrait was effectively conserved and returned to the Jassim family, BACC conservators gained new skills from collaborating experts, and the pilot program demonstrated a valuable approach for future projects. This initiative prompted BACC to reconsider its role in community service and affordability. Can we truly serve our community if only those who can afford treatment benefit? Are these issues for only nonprofits to address? While much remains to be explored, the experience has reinforced BACC’s commitment to addressing these challenges.

The 1896 residence of Caroline and John Jacob Astor IV on Fifth Avenue in New York City was designed by architect Richard Morris Hunt and renovated in 1910 by Carrere and Hastings, two of the most prominent architects of America’s Gilded Age. The mansion contained reproduction boiserie period rooms produced by the French interior decorating firm Jules Allard et Fils, emulating the tradition of ornately carved and gilded wood paneling of the 17th and 18th centuries in France. Prior to demolition of the Astor residence, two of these rooms—the Cream Salon and Library—were purchased in 1926 by John Ringling and soon after installed as period rooms in the John and Mable Ringling Museum of Art in Sarasota, Florida. In addition to the 1910 renovation, the period rooms had received later alterations and repairs, including overpainting of all painted paneling and much of the gilded ornament.

In 2023, EverGreene Architectural Arts was retained by the museum to elaborate upon earlier investigations, to characterize historic finishes in the rooms and carry out condition assessments and treatment testing. The goal was to better understand the boiserie techniques and develop methods for the appropriate conservation of the wood, gilding, painted finishes, and clear coatings on the wood paneling.

In this study, a more refined understanding of Jules Allard’s manufacturing and decorating processes was achieved. In particular, Allard drew upon traditional 17th-century French architectural gilding techniques, while also using more contemporary methods to enhance the depth and dimensionality of gilded surfaces. Visual examination combined with exposure windows and overpaint removal testing, in conjunction with optical microscopy and instrumental analysis, helped to confirm that Allard created desired visual effects by applying sanded boles, juxtaposing oil gilding and water gilding techniques, selectively burnishing the gold, and toning with shellac. In addition to identifying Allard’s 19th-century manufacturing methods, including the incorporation of wood veneers, the results of this investigation suggested the use of salvaged elements from authentic boiserie.

Xanthan-konjac/agar double-network hydrogels, a recent addition to the conservation cleaning toolkit, are thermoreversible, optically clear, cohesive, flexible, conformable, and elastic hydrogels capable of controlled delivery of a broad range of aqueous preparations, some organic solvents, and microemulsions. The development of these hydrogels is described in a separate submission.

Here, a series of case studies illustrate successful applications of these gels for the cleaning of easel paintings, painted surfaces, East Asian export lacquer, gilded surfaces, and works of art on paper, highlighting potential uses and limitations for these versatile formulations. Taken together, we present a model for early dissemination of emergent treatment materials, embracing a feedback loop to refine production and application techniques.

In 1924, while looking into ways to utilize southern yellow pine sawmill waste, William H. Mason invented a process to create a new type of hardboard. Within a year, he established a plant in Laurel, Mississippi to manufacture his new material. By 1926, Mason applied for, and was awarded, several patents for this new engineered hardboard that would be known as Masonite. Developed at the beginning of the Great Depression, and over the next 100 years, its affordability made it a popular material for use in homes, design, and art.

Soon after production began, Masonite was being used by artists.  An advertisement for Masonite in the June 1928 issue of Scientific American asked: “Where will this grainless wood be used next?” and “Did you know… that it is in daily service at the Chicago Art Institute as artist’s boards?“  It was in the paintings of Chicago-based Regionalist painters including Grant Wood and Thomas Hart Benton that we first find Masonite being widely used. It could be said that the rise of Masonite parallels the rise of American Regionalism and Social or Urban Realism painting in the 1930s, movements that represented a direct reaction against European Modernist painting. Rejecting not only traditional European subject matter but also traditional painting materials, Masonite was both affordable and readily available.

However, American painters were not the only artists who reached for Masonite in their attempt to upend the traditional hierarchy of painting materials and subject matter. The Catalan painter, Joan Miro, famously used Masonite in a series of 27 paintings in his attempt to do just that –to “assassinate painting” -between the years of 1927 and 1937 By 1940, in order to ramp up hardboard production, Masonite had licensed manufacturing facilities in Australia, Canada, Italy and Sweden. Its use as a painting support quickly spread across the globe.

Scholars of art materials and techniques, including Ralph Mayer, have written about the use of Masonite in making art. The changes in advice over subsequent editions reveal a changing understanding of the pros and cons of Masonite’s properties. Sorting out the history and details of Masonite production and how this has changed over time as well as the history of its use will help us more accurately understand the role of Masonite as an art material and why, at times, problems arise in its use.  

Bartolomeo Vivarini’s 1485 monumental altarpiece Virgin and the Dead Christ with the Ascension and Saints consists of a central polychrome sculpture surrounded by nine panel paintings all enclosed in the original ornate gilded frame. It is signed on the base of the Pietà: FACTVM VENETIIS PER BARTOLOMEVM VIVARINVM DE MVRIANO PINXIT 1485 (“Made in Venice by Bartolomeo Vivarini of Murano he painted it 1485”). Though the altarpiece was dismantled when it was removed from its original location in current-day Croatia in 1876, it is believed to be a completely intact work. The work has been in the collection of the Museum of Fine Arts, Boston (MFA) since 1901, with the various elements receiving different degrees of treatment over the past century. As a result of this uneven treatment history, the altarpiece has never read as a unified work of art. 

A major collaborative conservation treatment, supported by technical and scientific research, was carried out between 2018-2024 with the aim of finally bringing all the elements of the altarpiece into a cohesive whole. This presentation explores the ways in which distinct conservation specialties approached the treatment working in tandem with our research scientists and curators. 

Each element of the altarpiece was documented and examined thoroughly using techniques such as X-radiography, UV fluorescence, and infrared reflectography. The structure of the Pietà was investigated with CT-scanning at Massachusetts General Hospital. The materials (pigments, varnishes, gilding) were analyzed to better understand their composition and determine if the same materials were used consistently throughout, using methods including optical microscopy, Fourier-transform infrared spectroscopy, X-ray fluorescence, Raman spectroscopy, scanning electron microscopy, and energy dispersive X-ray spectroscopy.

Structural work was carried out on all the elements to stabilize splitting or cracking of the wooden substrates and strengthen areas of insect damage.  Some of the panels were sent to the Metropolitan Museum of Art Paintings Conservation Studio for more specialized treatment.  

Treatment was carried out simultaneously in the Paintings, Objects, and Frame Conservation studios, all of which are now in proximity, along with the Conservation Science department, in the MFA’s newly renovated Conservation Center. At several points in the treatment process the various parts of the altarpiece were brought together and reviewed with the entire team, including curatorial colleagues, to make sure that the levels of first cleaning and then compensation remained consistent. As treatment progressed, previously unnoticed or obscured details shared by the different pieces emerged, highlighting the complementary relationship among painting, sculpture, and frame. These visual cues were bolstered by the results of scientific analysis, which more firmly tied the works together. 

This project, completed in the spring of this year (2024), was an exciting opportunity for many of the divisions of the Conservation Department to collaborate on treatment and analysis. It led to fruitful exchanges of methods and different uses of materials and has built a framework for more collaborative treatment projects in the future.

Dendrochronology is a method of dating the age of wood, based on the measurement of tree ring widths followed by statistical comparison with master chronologies. Dendrochronology is used widely in the study and authentication of artworks, particularly furniture, panel paintings, and sculptures. In traditional dendrochronology this involves destructive surface preparation, macro photography, and manual ring counting. On painted surfaces or inlaid panels however, the tree rings are often not accessible to retrieve this information. X-ray imaging has therefore been used with success to obtain virtual cross-sections of objects without invasive methods. A proven method is CT scanning, which provides a three-dimensional image of the object, which can be virtually 'sliced' to obtain images of the tree rings. Recently, fast digital radiography detectors with high resolution have become available that can be combined with commercially available digital turntables to rapidly generate large numbers of radiographs of a single object at fixed angular increments. With these, it is now possible to generate full X-ray tomographic reconstructions (CT scans) using equipment available in many museum radiography laboratories. This eliminates the need for dedicated CT equipment or the transport of artworks to specialized facilities.

Large flat panels of wood, such as those used in furniture and panel paintings, pose difficult problems for conventional tomography because it can be difficult or impossible to rotate the entire panel within the field of view, and because the thickness of wood presented to the X-ray beam varies so dramatically as it is rotated.

In this presentation, we will present a solution to the challenge of large panels by obtaining X-ray images in a limited angular range. The resulting tomographic reconstruction has lower resolution in depth, but tree rings are still clearly resolved. The creation of a full 3D reconstruction means that obscuring elements such as marquetry, paint, and cradles can be virtually stripped away. We take an extra step by then using imaging processing methods to automatically measure the tree rings along the full 3D volume, thus averaging thousands of measurements and yielding precise and robust measurements. This method was developed using only the in-house X-ray imaging equipment of the J. Paul Getty Museum – which consists of a digital detector and a simple computer-controlled turntable. We demonstrate the method and prove that it works on test planks first. The obtained measurements are compared to traditional measurements made by three dendrochronologists. We then continue to apply the method on a case study object from the J. Paul Getty Museum. This method should allow many more artworks and architectural elements to be dated by dendrochronology than ever before.

We combine the expertise of dendrochronologists, conservators, X-ray scientists and computer scientists in a highly interdisciplinary project. The project is a collaboration between the J. Paul Getty Museum (Los Angeles) and the Center for Mathematics and Computer Science (Amsterdam).

The recent conservation treatment of a fifteenth-century Spanish altarpiece at the Conservation Center of the Institute of Fine Arts, New York University provided an opportunity to explore aspects of collaboration past and present. In this talk we will share recent research on the materials, techniques, and workshop practices of the Saint John the Baptist altarpiece (ca. 1415-20), a fragmentarily preserved retable attributed to the Aragonese painter Blasco de Grañén and now in the collection of the San Diego Museum of Art. The surviving panels of what was once a larger structure include a monumental central depiction of John the Baptist flanked by four scenes from the saint’s life. The treatment of the painting presented the opportunity for its examination, which was carried out using an array of techniques including binocular microscopy, x-ray fluorescence spectrometry (XRF), infrared reflectography, x-radiography, cross-sections, scanning electron microscopy (SEM-EDX), and Raman spectroscopy. Physical and stylistic aspects suggested aspects of cooperation within the Zaragosa workshop and offered information on the retable’s original construction and its conservation history. Salient features of the painting’s facture include its freely incised preparatory drawing and its innovative use of metal leaf in the rendering of textiles. It shows both similarities and differences with contemporary art in Spain and Italy. Through this research, we contribute to the still-understudied field of fifteenth-century Spanish and especially Aragonese painting; though a few publications have appeared recently, there is little information on the methods of many important workshops, nor on the commonalities and variations in the period’s artistic practice.

The treatment and technical study of the five panels was carried out within the Kress Program in Paintings Conservation at the Conservation Center by four students and one instructor and under the guidance of additional colleagues. The project provided an opportunity to work together as a group to examine and treat a large composite object; to coordinate, in both cleaning and retouching, the unified presentation of an array of panels in different conditions; and to collaborate in scientific investigation and writing. The talk will hence also reflect upon that experience within an educational context. It will sketch the division of research by subject and summarize the discussions and challenges that arose through the processes of restoration and scholarship. The desideratum of collaboration brought a heightened awareness of the painting’s original materials and our own conservation methods, as this fragmentary object presented many variations in condition and even in response to the same treatment steps. With its numerous, coordinated moving parts and apprenticeship-like structure, this project created a kind of modern analogue to the traditional workshop in which the retable was made.