Posters

24. The Gypsum Windows with Engaged Colored Glasses from Egypt: A Case Study in Conservation
    Dr. Badawi Ismael, Conservation and Restoration Department Manager, Valley South University, Qena, Egypt; Ahmed Eldomiyaty, Conservator, University of Cairo Graduate Student; and Anton Rajer, Instructor, University of Wisconsin

    For over one thousand years there has been a tradition in Egypt of making window frames from plaster of Paris lime mortars. We call this tradition “Egyptian Gypsum Windows” after the material used. In addition, because of the long history of glassmaking in Egypt these windows have inserts of colored glass. The windows are found in many locations such as homes, mosques, palaces, and schools. The earliest period for such windows was in the Tolonic period (868-905 AD), but was not decorated with the colored glass. During the Islamic Fatimid period (969-1171 AD) colored glass was introduced, especially in Cairo. The Mameluke Period (1250-1517 AD) saw a flourishing of the arts with large and ornate carvings in gypsum and the use of multi-colored glass. Technological innovations in this period included double sided decorated frames and refinement of decorative designs which is considered the “Golden Age” in gypsum windows.

    Later, in the Ottoman the period (1517-1798) gypsum windows became smaller and more refined as architects emphasized smaller structures with greater refinement. The finest examples of such windows are found in an extended architectural balcony called Mashrabia in Arabic. These elaborate balcony features are made of wood, and decorated with gypsum windows for light.

    Our research has concentrated on examination and treatment of these fragile windows. Physical examination and technical analysis with x-ray diffraction of the plaster provided us with scientific data about the nature of the materials. We made several models to test our theories about the materials used in making the gypsum windows. We found that a combination of gypsum, limestone powder, and small amounts of sand with 1% PVA in water based emulsion improved the properties of the materials. Our research is on-going in this topic. To date we have treated about 80 windows at the Bayet el Razzaz house, Cairo, from the 15th - 18th centuries, classical Ottoman period. We are also conducting additional research to find traditional craftsmen who may have made or repaired these fragile ancient windows. Our conservation efforts have included stabilization of the frames, glass conservation or replacement of glass when necessary, and an integrated approach with other allied colleagues.We thank USAID, the American research center, and Dr. Alaa Elhabashi, project manager.

    (Poster download not available)



25. Examining Leather Treatments and Dressings Using Microscopy
    Sonja Jordan-Mowery, Director of Conservation and Preservation, Principle Investigator, Heritage Science for Conservation, Johns Hopkins University, The Sheridan Libraries, Department of Conservation and Preservation
    

    Leather is a highly complex material created as a result of tanning skins of animals and its use as a cover material for books dates to the beginning of the codex. The tanning process for leather has changed over the centuries. Prior to 17th century, leather was of a fine quality and lasted very long in contrast to leather produced from the 17th to the 20th century which shows rapid degradation. During the 20th century, conservators responded to poor quality leather by introducing a variety of leather treatments thought to be beneficial for leather. Many formulations have been used including, potassium lactate to serve as a buffering agent for internal acids, neat’s foot oil and lanolin to serve as a lubricant, Klucel-G in ethanol to serve as a consolidant for degraded leather, and Renaissance Wax as a finisher and leather sealant.

    While some of these treatments have fallen into disfavor among conservators, others continue to be used for extreme degradation where no other alternatives exist. While conservators can see the effect of treatments intended to correct mechanical failure, they are disadvantaged from seeing and thus understanding the effects or the value of these treatments on the leather structure itself.

    From 1980 to 1983, conservation staff at Johns Hopkins identified and recorded several hundred calfskin bindings from the 16th – 20th century for leather treatment. Carolyn Horton’s two step treatment of potassium lactate in solution and the U.S. Department of Agriculture’s leather dressing formula were systematically applied. During a systematic preservation assessment of this collection, current conservation staff began a qualitative assessment of the treated leathers.

    In conjunction with this year’s Annual Meeting, this poster presents a series of high magnification images taken with a Zeiss AxioImager of historic and current leather conservation treatments. In addition to the conservator’s visual inspection to determine aesthetic and mechanical performance, the Zeiss Axio-imager M1m has the capacity to view samples from reflected bright field, darkfield, differential interference contrast imaging and fluorescence microscopy, thus enabling the conservator to view the both film formation and degree of penetration of surface dressings. Microscopic analysis will provide a comparative means of qualitative assessment of various dressings. Images of these past treatments were compared with images of surface treatments currently used by conservators: Klucel G, SC6000, and Renaissance Wax. Resulting images from the AxioImager M1m will be presented in the Image Gallery of the Andrew W. Mellon Heritage Science for Conservation Project at the Sheridan Libraries, Johns Hopkins University. The image gallery will make this information accessible to conservation professionals and add to the body of literature already available. Access to such an image gallery will provide a valuable resource and enable conservators to better understand conservation practices.

    (Poster download not available)



26. Stabilizing a Vision: The Investigation and Treatment of Southwestern Pottery at the Barnes Foundation
    Lara Kaplan, Conservator in Private Practice, Lara Kaplan Objects Conservation, LLC

    Among the masterpiece paintings and other works at the Barnes Foundation is a small collection of historic Southwestern Pueblo pottery. Amassed in the early 1930s, this group of 49 vessels contains many significant pieces, and also provides insights into Dr. Barnes aesthetic vision. In addition, correspondence and purchasing records in the Foundation’s archives give a fascinating glimpse into the Native American curio trade at that time.

    Left largely undisturbed since being acquired, the pottery had deteriorated and was in need of scholarly investigation and conservation care. The most pressing condition concerns included pervasive mold growth, soluble salt efflorescence, friable surfaces, and old repairs and overpaint that had failed or discolored. A generous grant from The Henry Luce Foundation allowed for the objects to be thoroughly researched, analyzed, examined, and treated.

    Though the main purpose of treatment was stabilization, another goal was to return the objects to a closer approximation of how they would have looked when Dr. Barnes acquired them. Past restorations in particular were seen as an important part of the history of the objects and these, along with evidence of pre-collection use, were kept as intact as possible. One of the most interesting—and challenging—aspects of the project was to preserve the old restorations within the context of current conservation practices for Pueblo pottery. This poster will describe the research, analysis, and treatment that allowed both for the preservation of the pottery and Dr. Barnes’ vision.

    (Poster download not available)



27. Study of Aging Behaviors of Mechanical Strength, Optical Properties, and Chemical Composite of Paper through Accelerated Aging Based on Papermakers’ Sizing Methods
    Sa Yong Lee, Andrew W. Mellon Post-Doctoral Fellow, John Baty, Andrew W. Mellon Post-Doctoral Fellow, and William Minter, Senior Project Conservator, Johns Hopkins University, The Sheridan Libraries, Department of Conservation and Preservation
    

    The alum-buffered rosin sizing had been used primarily as a papermaker’s friend to impart water-resistance to mass-produced paper internally until conservators noted a surprising phenomenon: the paper used in certain books produced in the 1700s seemed to be conditionally much better than the paper used typical books made during the late 1800s and 1900s. This phenomenon was studied by extracting the paper with distilled water and measuring the pH. A strong correlation was found between the extract pH of paper and the loss of paper strength. The alum changed its face from a papermaker’s friend to a very acidic guy to make the paper brittle during storage.

    Besides internal sizing, it has been used from an ancient time to coat a film of starch or other materials in order to impart water-resistance on the surface of paper. This traditional way has been continuously improved up to today to increase surface strength and resistance to the force of tacky inks in lithographic printing. This method also compensates the strength loss due to the high amount of filler added into paper during manufacturing.

    There are some researchers who reported the relations between the embrittlement of paper and various sizing methods. However, it is hard to find literature which reports the changes of paper properties and performances depending on the combinations of internal and surface sizing methods with various accelerated aging conditions which mimic the real and include the variations of time, temperature, and relative humidity.

    The aging behaviors in mechanical strength, opacity, surface topography, surface chemical composition and performances of paper were studied depending on the combinations of internal and surface sizing methods after the deterioration of the sized paper with variations of accelerated aging conditions (time, relative humidity, and temperature). The differences in paper strength, opacity, and performance after treating the aged samples with different types of conservators’ sizing methods and different applications were studied. The data acquired from this study provide us the background information to choose the proper one among conservators’ sizing and coating methods.

    (Poster download not available)



28. Examining Conservation Techniques Using Microscopy: A Comparison of Wheat Starch Paste Preparation Methods
    Crystal Maitland, Paper Conservator, Johns Hopkins University Sheridan Libraries
    

    Paper conservators are very particular about their paste-making methods, each arguing that their method of preparation is the most effective. There are a myriad of variables in preparation. Some choose to pre-soak their starch, others debate the methods of sieving, working, and kneading the paste after it is cooked. Perhaps the most controversial question is about the merits of cooking paste with a cook and stir, a double boiler, or using a microwave oven. Storage methods for paste, whether in the refrigerator, in a syringe, or under water, are equally contested.

    This project proposes to prepare paste by numerous recipes and cast each separate batch as a thin film. Using the Zeiss Axio-imager M1m microscope it will be possible to use reflected bright field, dark field, and differential interference contrast imaging and fluorescence microscopy to view the starch film and granule properties as a function of preparation method. This microscopic analysis will provide a comparative means of qualitative, or perhaps even a semi-quantitative assessment of paste preparation and storage methods. An image gallery presented on the web as a part of the Andrew W. Mellon, Heritage Science for Conservation Project at the Sheridan Libraries, Johns Hopkins University will allow this information to be accessible to the conservation profession. Adding to the body of literature, this research can help guide paper conservators in their choice of paste preparation methods.

    (Poster download not available)



29. New Approaches in the Field Laboratory of Kaman-Kalehöyük 
    Melissa Mariano, Preventive Conservator; Alice Boccia Paterakis, Director of Conservation, Japanese Institute of Anatolian Archaeology, Kaman-Kalehöyük Excavation, Turkey; and Colleen Healey, Objects Conservator

    At most archaeological sites the summer field season is short-lived but intense. The urgency to complete as much as possible is felt by conservation teams, whose responsibilities over the field season, and over the site’s life, continue to increase and expand. Two important tasks which are often the most difficult to finalize before the season expires are the completion of treatments to all finds and the surveying of growing collections in storage. During the 2009 season at the site of Kaman-Kalehöyük in central Turkey, solutions have been found to remedy these issues successfully to benefit both the site’s collections and its conservation department.

    During her first field season as Conservation Director at Kaman-Kalehöyük, Alice Boccia Paterakis evaluated treatment protocols for metal objects. She found that the standard procedure, a series of lengthy and toxic alkaline sulfite baths and carcinogenic corrosion inhibitors, was not sufficiently effective to continue using in a field lab environment. Paterakis also reviewed results from ongoing research at Kaman-Kalehöyük on anoxic and desiccant microenvironments for metals, using a product called the RP System by Mitsubishi Gas and Chemical Company. The system is non-toxic and easy to use, and metal finds continued to remain stable after 8 years of enclosure.

    In the summer of 2009, use of the RP System was instituted as the standard protocol for metal finds after mechanical cleaning, and when objects cannot be treated before the closure of the field lab, they are placed in these microenvironments and kept stable until the following field season. The long-term goal at Kaman-Kalehöyük is to eventually house most of the metals collection held in storage within these microenvironments.

    Another yearly assignment for which the site’s conservation team is responsible is to survey the metals collection. For the 2009 season, Paterakis assigned preventive conservator Melissa Mariano to take on the survey in addition to many other preventive tasks, including object mounting and environmental monitoring. During the survey, Mariano was able to isolate hundreds of objects showing signs of active corrosion and rehouse them into individual RP System microenvironments, saving some objects from complete decay.

    As the Japanese Institute of Anatolian Archaeology at Kaman Kalehöyük expands and begins excavation campaigns on two additional mounds this year, it was crucial to implement modifications to treatment protocols and division of work within the lab during the 2009 season. These changes show forward thinking and the lab’s continued commitment to health and safety and preventive measures, preferring simple, safe, and time-effective approaches over standard, grandfathered systems.

    (Poster download not available)



30. Nanoparticle Application to Archeological Cordage
    Molly McGath, Graduate Research Student, Nancy Odegaard, Conservator, Head of Preservation, and Werner Zimmt, Scientist, Arizona State Museum, University of Arizona

    The Arizona State Museum is home to over 22,000 pieces of whole archaeological basketry, textiles and cordage. While whole pieces of archaeological cordage from the Southwest have been preserved, their continued existence is threatened by their inherent fragility. This research addresses the problem of deteriorating cultural objects composed of cellulose. The preservation of these objects is proposed by introducing nanoparticulate calcium hydroxide in hopes that this will serve to neutralize the acid that is causing the break-down of the cellulose. The aim of this research is to evaluate a methodology for stabilization of fragile archaeological textiles, basketry, and heritage objects. This poster reviews the synthesis of the nanoparticulate calcium hydroxide, the creation of an experimental matrix, the evaluation methodology for understanding the kinetics of penetration into various cellulose substrates for various carrier solutions containing nanoparticles of calcium hydroxide, and the evaluation of the effect of the application of these nanoparticles to a fragile cellulose matrix.

    (Poster download not available)



31. Weavers Look for a Way to Preserve Their Heritage
    Hector Meneses, textile Conservator, Museo Textil de Oaxaca, Mexico
    

    Teotitlán del Valle is a Zapotec community located 28 km from the city of Oaxaca, in southern México. Almost everyone in Teotitlán is involved in textile production, and the tradition is often passed on from fathers to sons. In addition to traditional weavings, such as sarapes and rugs, weavers have been exploring ways to diversify their production by creating hand-bags, backpacks, purses, and accessories. The Community Museum of Teotitlán del Valle (MCTV), established in 1993, shows the town’s history from pre-Columbian times until now. The textiles on display are mainly sarapes and blankets woven between 1950 and 1970, and have been on permanent display for over sixteen years. The textiles now show a heavy coating of dust, there is some infestation causing rips and holes, and the mounting system has created distortions. In August 2009, the MCTV’s Board contacted the Textile Museum of Oaxaca (MTO) to get advice on care, display, and storage of their textiles. The MTO decided to create a joint project with the MCTV. The MTO will assess the condition of the textiles, and their storage and exhibit standards, during an upcoming rennovation to the MCTV building. A preventive conservation program for textiles will also be established. The conservation treatments will be co-ordinated with the National School of Conservation, Restoration, and Museum Studies—“Manuel del Castillo Negrete”—in Mexico City. Conservation students will do internships in Teotitlán, where the community will absorb some expenses such as lodging and meals. The community will also donate some materials needed for treatment. This collaboration demonstrates how the initiative of the community to preserve their own heritage has been a vital factor in its success. Active participation of the community increases the likelihood of long-term impact on their textiles, even without a full-time conservator on their side.     

    (Poster download not available)



32. Risk-Based Decision Making for Collections: The ICCROM-CCI-ICN Course, the Method, and Associated Tools 
    Stefan Michalski, Senior Conservation Scientist, Canadian Conservation Institute
    

    Since 2002, ICCROM, the Canadian Conservation Institute (CCI), and the Instituut Collectie Nederland (ICN) have collaborated on the development and delivery of a course entitled Preventive Conservation: Reducing Risks to Collections hosted in Rome (2005), Ottawa (2006), Sibiu (2007), Beijing (2009), and Quito (2009). As a result of sharing the method with mid-career professionals from all regions of the world, as well as incorporating new developments from various risk assessment projects and services pursued independently by each partner, we have refined the risk assessment method used for the course and developed support tools. These include a short manual, a long handbook (currently in draft form), and a database for entering individual risks, carrying out all necessary computations in the background, creating various graphs for comparing risks, and generating reports for clients. The structure of the overall method, and the basic terminology, was based on the Australian and New Zealand standard for Risk Management (RM), which is itself based on a conventional model of the RM process. The model suggests five sequential steps: establish context, identify risks, analyze risks, evaluate risks, and treat risks. There are two ongoing processes: communicate and consult, monitor and review. Three components are used to quantify a collection risk, based on an earlier CCI proposal called the ABC method where A is rate or frequency, B is loss of value to each affected object, and C is fraction of the collection affected. The latter component is now measured in terms of collection value, using the Collection Value Pie, developed during the course by J.L Pedersoli of ICCROM. The focus of CCI’s contribution in the last two years has been as lead author of the manual, the handbook, and the database. We are also pursuing development of our own collection assessment service this year, using the method and the support tools.

    The risk-based approach is taught not only for the purposes of comprehensive risk assessments, but also as a quantified approach to specific decisions. It can incorporate intangible values as well as the material science of deterioration. It can incorporate heritage buildings and their components as part of the institution’s collections. Course participants universally enjoy the final section of the course when a day long exercise focuses on a specific collection management decision that conventionally can seem an insoluble dilemma. Examples have  included a choice between moving abandoned churches to an eco-museum, or leaving them in-situ, a choice between allowing revenue generating parties in a gallery with wall paintings, or risking loss of revenue, a choice between restricting visitor numbers in a vulnerable and recently restored building, or allowing ten times the visitor flow, and ten times the access.

    (Poster download not available)



33. 33. Evaporation of Fatty Acids and Formation of Whitish Deposits on the Inside of the Glass of Microclimate Frames in the Mauritshuis: A Case Study in the Mauritshuis
    Petria Noble, Head of Paintings Conservation, and Annelies Van Loon, Paintings Research Scientist, Royal Picture Gallery Mauritshuis, The Netherlands
    

    Since the early 1990s, paintings in the Royal Picture Gallery Mauritshuis (The Hague) have been routinely glazed to prevent damage from vandalism. Panels, and paste-lined paintings, that are deemed fit to travel, are sealed in specially adapted frames to prevent/minimize climate fluctuations, so-called microclimate frames, consisting of a UV safety glass (Schott Microgard Protect) and a polycarbonate backboard (Lexan). The rebate and the backboard are sealed with an aluminium barrier foil. Over the course of many years hazy deposits, often referred to as ghost transferred or mirror images, have been seen to regularly form on the inside of the glass. The deposits are greasy in nature and depending on thickness, are grayish or whitish in appearance and can severely diminish viewing of the art work. Since 2001, hazy deposits have been removed from the glass on more than 200 paintings in the Mauritshuis.
    This poster presents a case study regarding whitish deposits that formed on the inside of the glass of the microclimate frame in which Gerrit Dou’s The Young Mother (1968, Mauritshuis inv. no. 32) was housed. The heaviest deposits, corresponding to dark reddish brown and black areas of the painting, were seen to form over a period of a few months, from March to July 2007, when the picture was hanging on an exterior, southwest-facing wall of the museum. The dark areas of the painting, built up in multiple layers of oil-rich paint containing a high proportion of chalk, in addition to umber, bone black, red ochre and possibly also asphalt are considered to provide a rich source of free fatty acids. Since 1815, the picture has also undergone some 16 documented treatments involving solvents, which may have led to increased mobilisation of the fatty acids in the paint; the dammar varnish on the picture dates to the last treatment of the painting in 1987.

    Fourier transform infrared spectroscopy and energy dispersive x-ray analysis carried out by the Netherlands Institute of Cultural Heritage, Amsterdam, revealed that the deposits consist of a sodium carboxylate, or a mixture of sodium carboxylates, such as sodium palmitate and sodium stearate, indicating an origin from the oil binding medium. Precise monitoring of the climate conditions carried out on the southwest-facing wall by Technical University of Eindhoven from 2004-2006 demonstrated daily temperature fluctuations on this wall between 15.8ºC and 30.5ºC with a corresponding variation in relative humidity from 31-80%.

    It is hypothesized that a temperature gradient developed inside the microclimate frame as a result of contact with the warmed, poorly insulated exterior wall and/or exposure to direct sunlight through the partially open south-facing windows, causing free fatty acids to readily evaporate out of the paint. The deposition of fatty acids on the inside of the glass is considered to undergo a subsequent reaction with the sodium in the glass to form sodium soaps. The evaporation of fatty acids also occurs with unglazed paintings, but without being noticed, and possibly at a faster rate given the larger difference in concentration between the source and the surroundings. The results correspond with earlier published studies regarding ghost or transferred images on the inside of glass and fatty acid deposits found on the surface of paintings. As a result of this case study the Mauritshuis has now taken measures to improve the conditions of the southwest-facing exterior wall in the galleries. The design and construction of the microclimate frame is also being reviewed.

    (Poster download not available)

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