Last quarter we both had the opportunity to treat pre-Columbian Nayarit ceramic figurines from Mexico, on loan from the Southwest Museum of the American Indian Collection, Autry National Center. At first glance we thought the treatment would be pretty straightforward, but after a closer look it appeared to be anything but!
The surface and structure of the figurines are deceptively highly restored, which can be common for artifacts passing through the art market. In addition to reassembling the fragmented figurines, our goal is to document and identify old from new, and shed light onto the unknown pasts of these objects. We’re approaching the project with a range of tools including X-ray imaging, UV-induced visible fluorescence imaging, X-ray diffraction (XRD) analysis, and X-ray fluorescence (XRF) spectrometry. XRF analysis indicates the presence of lead and zinc on the surface of both figurines, which are common in modern pigments, though typically not found in pre-Columbian ceramics. Using XRF and XRD, we also detected the presence of plaster in some areas, a common restoration material for ceramics. While we work to try to piece our puzzles together, take a look at our projects!
Female Nayarit figurine before treatment. Southwest Museum of the American Indian Collection, Autry National Center, Los Angeles; 2232.G.33
Female Nayarit figurine during treatment: after reconstruction (left) and after gap-filling of the joins to stabilize fragments on the nose and lower section of the body (right). Southwest Museum of the American Indian Collection, Autry National Center, Los Angeles; 2232.G.33
Female Nayarit figurine after treatment. Southwest Museum of the American Indian Collection, Autry National Center, Los Angeles; 2232.G.33
Figure 5: Male Nayarit figurine, imaged under visible light (left), 415 λ induced visible fluorescence (center) and B&W image of UV induced visible fluorescence (right). Fluorescence imaging can help distinguish difference in material that cannot be detected under normal lighting conditions. It is common for restoration materials to fluoresce distinctly from original material. Southwest Museum of the American Indian Collection, Autry National Center, Los Angeles; 2232.G.28
X-ray image of Male Nayarit figurine taken from the back of the object at 45 kV. This imaging technique reveals that the body is composed of many fragments that have been previously restored. Southwest Museum of the American Indian Collection, Autry National Center, Los Angeles; 2232.G.28
XRF analysis was conducted on the rear supports at the bottom of the figurine. The spectrum shows presence of gypsum-based plaster due to the high calcium peak (CaKa1) and presence of a sulfur peak (S Ka1) indicating this is an area of restoration. The significant amounts of titanium (Ti Ka1) and manganese (Mn Ka1) may be from modern pigments used to paint the plaster surface. Southwest Museum of the American Indian Collection, Autry National Center, Los Angeles; 2232.G.28
Papers The ‘dead-bucket’: An inexperienced conservator’s guide for evaluating setbacks Ayesha Fuentes and Geneva Griswold
Setbacks are an often-unacknowledged reality of conservation practices. This paper examines various types of setbacks, shortcomings, and mistakes in conservation practice, including unsuccessful treatments, errors in judgment, and the limits of intervention. While it may be tempting for a young conservator to anticipate these types of experiences as ‘failures,’ we argue that these situations provide opportunities for growth and development. While a senior professional may readily recognize the value in setbacks and contextualize them by drawing upon their past experiences, we seek to explore the ways in which a less seasoned practitioner may productively reinterpret or reevaluate such situations in terms of our expectations, achievements, and sense of personal responsibility. Categories of setbacks will be illustrated with specific examples from personal experiences and those of our cohort-at-large as pre-program trainees and students.
This project was first inspired by the attempted re-treatment of a ceramic object during the Fall of 2011 at the UCLA/Getty Conservation Training Program. While the objectives of the assigned exercise were unmet — the object was returned to the lending institution in the same condition that it arrived at our training labs— the student learned appreciably about the effects of material degradation, the decision-making process for designating an object as un-treatable, and the ethical considerations such conclusions require. Further examples of setbacks include errors in judgment — such as removing original polychromy by wheeling a tall, wooden sculpture into a low door frame — and a lack of self-awareness with drastic consequences for object safety when a ceramic figure was knocked off a table as a result of fatigue. By reflecting on and discussing the setbacks we encounter as inexperienced conservators, it is possible to glean lessons about our limitations and expectations of conservation practices, and to integrate these into our evolving working methods. Strategies for reevaluating these experiences include viewing them in terms of their positive role in developing long-term goals and practical methodologies as well as promoting a non-punitive and professional culture of honesty, humor, and acceptance. We hope that our attitude will help establish, in the words of Marincola and Maisey (2011), ‘a more fruitful learning culture’ for the benefit of both the field of conservation and its mission to protect and preserve historic and artistic materials.
We hope that by encouraging a collaborative and collective acknowledgement of our limits and, simply put, humanity, will help redefine learning goals for emerging conservation professionals. We believe that fostering an open dialogue amongst our peers, and eventually the conservation community-at-large, will promote a deeper understanding of our methods and the body of wisdom from which we draw as a discipline. Additionally, we would like to promote the idea and organization of an online, perhaps anonymous, forum for practitioners at all stages of their careers to report similar experiences.
Unmasking the surface: A technical analysis of eight polychrome Kuba masks Geneva Griswold and Madeleine Neiman
The Kuba region, positioned in south-central Democratic Republic of Congo, between the Sankuru, Kasai, and Lulua Rivers, is widely renowned for its vibrant masking tradition. Funerals and initiation ceremonies often include a masquerade, honoring the initiate through dance, masks, clothing, and associated accouterments. While the fields of anthropology and art history have devoted significant time and study to the Kuba masquerade traditions, technical analysis of the methods and materials used in the masks’ fabrication is limited. During the fall of 2011, the first year students at the UCLA/Getty Program in collaboration with their colleagues in the Material Science and Archaeology departments conducted a technical study of a suite of eight Kuba masks in the Fowler Museum’s Wellcome Trust collection. Students employed both non-invasive and invasive techniques including: forensic imaging, X-ray fluorescence spectroscopy (XRF), and ultra-violet-visible-near-infrared (UV-Vis-NIR) spectroscopy, optical microscopy under white, plane, and cross-polarized light (PLM), X-ray diffraction spectroscopy (XRD), scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS), and microchemical testing. This paper endeavors to place the information gathered within the larger context of Kuba scholarship, by highlighting the common aspects between the masks as well as their variability. Examination of this collection of Kuba masks contributes to further understanding of the masks’ construction, adaptation, and use, thereby promoting a deeper and fuller understanding of the objects as historic artifacts as well as aid in determining proper methods of handling, storage, display, and conservation.
Posters Treatment of eagle and northern flicker feathers on a Native American shield cover Tessa de Alarcon
Stabilization of eagle and Northern flicker feathers (Colaptes aurates) was undertaken on a Plains shield cover in the collection of the University of Pennsylvania Museum of Archaeology and Anthropology. Material testing for vane repair and loss compensation was conducted on damaged turkey feathers. Vane repair testing included bridges of hair silk adhered with 5% methyl cellulose as well as linings of light weight Japanese tissue, Hollytex (spunbonded polyester), and silk Crepeline each adhered with 2% methyl cellulose, Lascaux 360, Lascaux 498, or AYAF (polyvinyl acetate resin). Both of the Lascaux adhesives and the AYAF were painted onto the supports and reactivated with heat or solvents. Methyl cellulose performed better than the other adhesives and the hair silk bridges were the least visually intrusive and provided the best support. Loss compensation methods tested included two weights of Japanese tissue (light weight and heavy weight), as well as Hollytex adhered with 2% methyl cellulose. Since methyl cellulose performed better than the other adhesives, it was the only one tested. The lightweight Japanese tissue adhered best in the loss compensation tests. Hair silk and Japanese tissue adhered with methyl cellulose were used on the shield cover feathers with good results.
The Significance of Surface in Central African Masks: Pigment Identification of Polychrome Wood masks from the Congo Geneva Griswold, Casey Mallinckrodt, Brittany Dolph
The treatment of surfaces in African masking traditions reflects the adaptation of materials for cultural ritual and use. This poster presents a study of surfaces using micro-analytic techniques, whose results provoke questions regarding the masks’ methods of manufacture, material adaptation, and provenance. The colors of different chemical composition and microstructure were sampled from a suite of eight polychrome wood masks from the Kuba region of the Democratic Republic of Congo. Dispersion and cross-section samples of the wood and pigments were analyzed using polarized light microscopy (PLM) and scanning electron microscopy (SEM) in order to ascertain their chemistry and composition. PLM enabled direct observation of optical characteristics relating to particle size, habit, relief, and color under plane polarized light, as well as crossed polarized light observation of birefringence and interference colors, when present. Such characteristics successfully identified the pigments applied on each mask, and facilitated the comparison of manufacturing techniques and materials within the suite. As well, PLM and SEM analyses corroborated evidence attained from XRF, XRD, UV/Vis/NIR, and SEM/EDX investigations. This investigation contributes to our understanding of Kuba mask materials and production, as well as highlights the role of microscopy and microanalysis in the study of African masking traditions.
Tunable Light Sources and Modified Cameras: Utilizing Imaging Techniques to Better Understand Ancient Art at the J. Paul Getty Museum Dawn Lohnas
Two relatively new imaging techniques, used by both the UCLA/Getty Conservation Program and the Getty Villa antiquities conservation laboratory, have recently been adopted to assist with the non-invasive analysis and documentation of artifacts. The UCLA/Getty Program utilizes a modified camera with an “alternate light source (ALS)” (Mini-CrimeScope®400), which is traditionally used in forensic science. Providing light at narrow band wavelengths using a series of filters, this equipment allows for easy analysis over a broad spectral range. Faintly painted figural outlines on a recently acquired lekythos in the Getty Villa collection were successfully photographed using this technique, and are now included on the object label in the museum’s galleries, illustrating how the vase once looked in antiquity. In addition to the ALS, scientists, conservators and students at the Getty make use of a modified camera system for capturing Visible-induced infrared luminescence of Egyptian blue. It can be used in-situ to confirm the identification of Egyptian blue without sampling, and has helped to identify areas of restoration, and areas of paint decoration that are difficult if not impossible to identify under normal lighting conditions. Several case studies involving these imaging techniques will be discussed.
Conservators are always looking for new techniques that will aid in the examination and documentation of art. The UCLA/Getty Program purchased a forensic light source, the Mini CrimeScope (from Horiba Scientific), to investigate its application in conservation. The CrimeScope is an alternate light source used by crime scene investigators to look for blood stains, latent fingerprints or any other forensic evidence they could utilize for solving crimes. The wavelength of the emitted light in the CrimeScope is controlled by filter wheels that allow material to be examined from ultraviolet to infrared. Instead of solving crimes, students in the conservation program have been using it to solve archaeological mysteries through the study of ancient and ethnographic objects. Artifacts analyzed include pre-Columbian ceramics and polychrome African wooden masks. They have been using the light source to look for evidence to answer questions about materials, technology and manufacture of artifacts, areas of deterioration and signs of previous conservation interventions. Our CrimeScope has also been used by colleagues at the J. Paul Getty Museum to look at the faint remains of a drawing on a white ground lekythos.
The CrimeScope is being employed to compliment other techniques of analysis and provide a first screening during the examination of materials. With the use of a forensic camera and a series of different camera filters the students have also been able to record the fluorescence and luminescence of materials and to see beneath their surface. The results are remarkable and we are currently exploring other potential applications of our CrimeScope to investigate and document different archaeological and ethnographic treasures.
The image above shows how the CrimeScope helped to highlight the decoration on a pre-Columbian vessel that was not as evident when viewed in visible light (left image) or ultraviolet (UV) light (central image). When examined in visible light, the decoration on the vessel is faint and obscured by burial deposits. Examination using a UV light at λexc max=365nm allowed for the decoration to be more visible. However, using the CrimeScope with a filter at λexc max=415nm the decoration was more distinctive and stood out. In particular the "S" shaped design on the upper left side of the vessel, which is slightly visible in the central image under UV, is much clearer in the image taken using the CrimeScope. (Vessel image courtesy of the Fowler Museum at UCLA. Photo taken by A. North, 1st year conservation student)
![Female Nayarit figurine before treatment. Southwest Museum of the American Indian Collection, Autry National Center, Los Angeles; [2232.G.33]](https://uclagettyprogram.files.wordpress.com/2014/05/dsc0047.jpg)
UCLA/Getty Conservation Program 