Category: Specialty Sessions

Posts on talks that were presented as part of the specialty sessions at AIC’s Annual Meeting

42nd Annual Meeting- OSG + RATS Session, May 30, “Blue, Red, and Wound All Over: Evaluating Condition Changes and Cleaning of Glass Disease on Beads” by Robin O’Hern and Kelly McHugh

Glass disease, weeping glass, glass deterioration, funky glass* (*author’s description)–just a few of the many names used to describe the degradation of glass beads that museums have observed as a white precipitate/cloudy appearance and/or cracking and splitting.  If you’ve observed this in your collection, take notice- Mellon Fellow in Objects Conservation, Robin O’Hern, is on the case.
O’Hern has taken advantage of the history of glass disease detection at the National Museum of the American Indian (NMAI) and begun evaluating how the different cleaning methods have fared over the years.  In 1999, Kelly McHugh (research supervisor and co-author) and Scott Carrlee performed a condition survey of the NMAI collection.  The collection was moved into a state-of-the-art storage facility after the survey, where the RH has remained constant, but at a higher level than recommended for glass pieces.  (The beads are present on composite pieces with hide, bone, shell, feather, hair, etc. and therefore the environmental controls must address as many materials as possible, not just glass.)  Some of the pieces were treated at that time, and others have been treated in the interim years.  Using the museum database, O’Hern found that 25% of the condition records that list glass beads as a material also list glass disease.  O’Hern has performed another survey, this time seeking to observe condition changes over the past 15 years in a selection of objects from the 1999 survey, to assess treatment technique (ie, which solvents worked best to reduce glass disease), and to discover susceptibility trends (which beads are the worst culprits).
To understand the beads, O’Hern provided background on history of use and manufacture.

  • Glass beads arrived after contact with Europeans in 1492
  • Pony beads were introduced after 1675
  • Wound beads were introduced after the late 17th century
  • Seed beads were introduced 1710-1840
  • Red beads were colored from copper in the 17th century, ruby red in the early 18th century, and selenium in the 1890’s
  • Blue beads were colored from copper or cobalt, but from 1640-1700, they were tin-rich
  • Beads can be made by pulling the heated glass, called “drawn,” or by winding heated glass around a rod, called “wound”
  • Glass is made from silica, alkali (to lower the melting point, but also makes it water soluble), and calcium carbonate (that turns to lime- it’s added to help stabilize the glass after the alkali)

There are several explanations for the cause of glass disease.  Too little or too much of the lime (part of the bead’s composition) may cause water to leach out of the glass matrix as ions that then form salt on the surface of the bead.  The environmental conditions, such as fluctuations in RH, or materials in proximity, such as semi-tanned hide, may accelerate glass disease.  As seen from the list above, the beads were manufactured over a range of time, in different ways, and in different places.
As you can tell, there are many factors to research when evaluating glass disease.  O’Hern addressed as many as possible while still managing the scope of the project.
Survey Results
Condition Change: By comparing condition of the beads today to past condition/treatment reports, 16% of the beads have more deterioration now than in 1999.  Measuring pH was used in addition to visual examination to determine condition.  Some beads that did not look bad had a higher pH (above 7), signaling glass disease.  Some beads that looked hazy did not have a higher pH, meaning no glass disease (perhaps hazy from manufacture).
Differing Manufacturing Techniques:  Wound beads have it worse than drawn beads–95% of wound beads have glass disease.  This could be because they have a compositional percentage of lime that is less stable.
Differing Colors: Black, red, and blue are the most disease-ridden.  O’Hern looked through the museum database and found that the entries with the most “glass disease” indicated had blue beads.  Blue beads are very clearly the “winner” of the glass disease competition, followed by red and black.
Treatment Techniques:  Here’s where it gets even more interesting.  The conservation literature and posts on the Objects Specialty Group list serve debate the use of three solvents to remove the salts on glass disease: water alone, ethanol alone, and a 1:1 water:ethanol mix.  By comparing the 1999 survey to her own results, O’Hern capitalized on real-time aging to observe how each solvent mixture fares over time.  Water-cleaned beads had a 50% rate of glass disease return; water:ethanol-cleaned had a slightly higher than 50% rate of return; ethanol-cleaned had the least amount of return at just under 50%.  However, when looking at the beads cleaned with ethanol over the same time period as those cleaned with 1:1 water:ethanol (removing the very oldest treatments), the rate of return for glass disease falls to 40%.
(Note: Acetone has also been listed as a solvent for cleaning glass beads, but since the NMAI doesn’t use acetone, it was not included in this research.)
Other Observations:
1. Measuring pH is essential because beads may look like they don’t have glass disease, but are actually more alkaline.  Measuring pH is also quick and easy- cut your pH strip to a small piece, slightly dampen it in deionized water, press it onto the bead for 3 seconds, and then determine any color change in the strip.
2. The most affected beads were those sewn onto hide, but the disease was present when beads were in contact with many other materials as well.
3. Although cleaning with ethanol is a better choice for long-term disease prevention, the solvent chosen should still depend on the substrate around the bead.
Advice from O’Hern:
1. Record treatment materials when removing glass disease.
2. Take BT and AT details of beads so you can easily compare for condition changes in the future.
3. Measure the pH of the beads… and RECORD THE RESULTS.
4. Have consistent monitoring of glass disease.
As an audience member, it’s always exciting to see a project that has results, especially on a topic that is not studied as extensively as it persists. This is definitely a postprint worth visiting for more details and results.
For other examples (and some “good” photographic examples), visit Ellen Carrlee’s project “What’s that White Stuff?” that she and (then WUDPAC graduate intern) Christa Pack reported on in Ellen’s blog: http://alaskawhitestuffid.wordpress.com/2011/08/09/glass/

42nd Annual Meeting – Joint PSG/WAG Session, May 31, 2014, “Recent Developments in the Evolution of Spring-loaded Secondary Supports for Previously Thinned Panel Paintings”, by Alan Miller and George Bisacca

In his presentation, Alan Miller, Assistant Conservator in Paintings Conservation at the Metropolitan Museum of Art in New York, showcased recent developments of spring-loaded secondary supports attached to the back of panel paintings.
He began by reviewing how usual 19th and 20th century treatment of warped panel paintings involved severe thinning of panels along with the application of wood “cradles” on their backs to straighten them and provide “support”. This portion of the presentation wonderfully complimented Karen French’s earlier talk on the evolution of the structural treatment of panel paintings at the Walters.
As Karen did in the morning, Alan discussed the consequences of past treatments on the panel and its painted surface. New treatment approaches have evolved over the past two decades with the development of flexible supports attached to the back of panels, allowing for the natural curvature of the wood and its movement in response to changes in relative humidity. Specific consideration was given to previously thinned panels, very vulnerable once their cradle is removed. Alan provided a review of the development of the spring mechanisms they developed with George Bisacca these past years, referring to the Getty Conservation Institute’s panel paintings initiative (link: http://getty.edu/conservation/our_projects/education/panelpaintings/panelpaintings_component1.html)
The presentation was generously illustrated with images of the various spring mechanisms developed at both the Istituto Superiore per la Conservazione ed il Restauro (ISCR) and later by Bisacca and Miller, explaining the pros and cons of each. For instance, the earlier conical spring designed at the Istituto allowed for much movement but required thickness of the wooden strainer attached to the back of the panel painting, an issue in terms of flexibility of the strainer, not to mention weight and volume. On the Met’s most recent strainers, which are much thinner, grooves are cut cross grain and filled with a silicon based material for added flexibility. Miller emphasized the importance of the number and placement of the springs attached to the back of a previously thinned panel.
He listed the criteria established for the development of spring mechanisms specifically designed for previously thinned panels: springs should be as small (contained) as possible to allow for a thin strainer, easy to adjust, economical and re-usable. Most recently their work has focused on a thin laser cut disk spring, associated with a flexible threaded nylon screw, which allows light weight, flexibility and fine adjustment.
This talk provided very valuable information on recent developments in the treatment approach of wooden panels, applicable not only to paintings but possibly to furniture or architectural wooden panels.

42nd Annual Meeting – Wooden Artifacts Group Session, May 29, 2014, “Review and interpretation of X-Rays of construction details of American seating Furniture”, by Gordon Hanlon

In his talk, Gordon Hanlon discussed a project that started at the Museum of Art Boston (MFA) in 2005 around a controversy regarding the date of manufacture of a side chair by Philadelphia furniture maker and carver Benjamin Randolph (1721-1791). In his 1972 book American Chairs, Queen Anne and Chippendale, John Kirk argued that a chair bearing a Randolph label and its mate – both in the Karolik Collection at the Museum of Fine Arts, Boston – were out of period. Consequently, both objects were removed from exhibition. Kirk’s analysis was refuted twenty six years later by Philip Zimmerman in an article published in American Furniture, entitled “Labeled Randolph Chairs Rediscovered”, available online at: http://www.chipstone.org/html/publications/1998AF/Zim/1998ZimIndex.html. While the Museum of Fine Arts was preparing for the opening of its new American wing, the Randolph chair was X-rayed to study its joinery. This examination confirmed Philip Zimmerman’s judgment that the chair’s construction was consistent with period manufacture techniques, most likely around 1765-75. This investigation was the start of a much larger campaign of study of chairs’ construction through X-Ray examination.
The MFA collection counts 278 American chairs, from early 17th c. to 1950, allowing for thorough comparison of construction techniques and tool marks associated with joinery. The Furniture laboratory started x-raying chairs as they came into the lab, which worked well in conjunction with the American wing project. One type of chairs did not lend itself well to that type of analysis: painted seats with lead based ground.
When film was used in the initial phase of this project, it was scanned at 300 dpi. The file was then enhanced in photoshop, using for instance the “unsharp mask” tool, then brightness and contrast adjustments. Many other options are of course available to reveal various levels of information on the image. The MFA recently switched to digital X-Ray, which seems to surpass film from Gordon’s point of view.
In order to compare information revealed by the X-Ray images, Gordon made mock-ups of joints and looked at a selection of bits. 36 chairs have been x-rayed so far. A few examples were illustrated in the talk, showing tenon and mortise joints as well as dowels.
To record the data gathered, TMS database showed some limitations, leading the lab to use Filemaker pro. The lab already had experience with this database as they used it for two previous projects: in 2005 for a study of historic fasteners (Chris White), and in 2008 for an investigation of painted furniture (Carola Schuller and Michelle Derrick). Currently Christine Schaette, who also gave a talk during this WAG session, is also using Filemaker pro to record her findings on inscriptions found on furniture. Gordon concluded his talk by inviting his colleagues to share results of their own examination of seats. This is something to investigate for WAG, to hopefully find a way to create a platform for everyone to share X-Rays of chairs.
 

42nd Annual Meeting – Photographic Materials, May 31, "Retouch Practices Revealed in the Thomas Walther Collection Project" by Lee Ann Daffner

MoMA‘s Thomas Walther collection contains over 340 photographs Walther collected from 1909 to 1949 in Eastern Europe, the United States, and Paris. Many of these photographs will be on exhibition at MoMA between November 08, 2014–April 26, 2015. The departments of Photography and Conservation at MoMA have been collaborating on researching this collection of Modernist photography which will culminate with a publication that will be available in early 2015 and a symposium on December 12, 2014. The results of this collaborative research will also be available on the OBJECT:PHOTO website which will include a timeline of Walther’s life and identification of photographs by location. The research Lee Ann presented at AIC focuses on artists’ working methods, specifically retouching techniques. Retouching can be done to either a print or a negative to enhance effects or mask imperfections. Retouching includes reductive techniques (such as scraping) versus additive techniques (painting, drawing, etc.), and an artist’s discretion to use any of these techniques can inform the viewer about the photographer’s intentions.
 
Summary by Greta Glaser, Owner of Photographs Conservation of DC

42nd Annual Meeting – Photographic Materials, May 30, "Preservation of Deborah Luster's One Big Self" by Theresa Andrews

Luster is a Louisiana based artist who began her own career in photography in 1988 after the death of her mother. Both her mother and grandmother were photographers. One Big Self is an artwork comprising 287 4″ x 5″ silver gelatin developed out photographs on aluminum plates, stored in a steel cabinet with three drawers, and a lamp on top of the cabinet to facilitate viewing. The photographs are portraits of Louisiana prison inmates taken between 1998 and 2002. On the back of each metal plate is a personal description of the person in each photograph. The artwork is intended to be interactive, allowing the viewer to handle the photographs and read the inscriptions, seeing the subjects as real people. The metal plates are covered in paint, followed by the gelatin emulsion layer used to print the photographic image which is selenium toned. Creating these plates is very labor intensive, and Luster only manages to produce three to four plates per day. She inscribes the personal information about the inmates on the plates with a dremel tool.
The San Francisco Museum of Modern Art (SFMoMA) was faced with the challenging task of displaying One Big Self in the way the artist intended – as an interactive work – after it was acquired in 2003. The security and physical preservation of the photographs were the two biggest threats to the work. The piece ended up being displayed alone in a room with one museum guard on duty at all times, which seemed appropriate in the context of the artwork’s subject matter. It was decided that only 200 plates would be displayed at any time, and twenty portraits were randomly selected to never be displayed. The plates that have been on display have indeed seen changes. Some plates have been caught in the drawers and become bent, edges of the emulsion on some plates have been abraded, and some of the plates have yellowed. Although the artist is dismayed at learning about the yellowing, the cost and time of replacing each plate as it becomes too worn to be viewed makes reprinting each portrait an inefficient solution. Out of the total 287 plates, excepting the 20 that will never be displayed, only 200 are on display at any given time, so 67 plates can still be swapped with any plates that become too damaged for exhibition.
 
Summary by Greta Glaser, Owner of Photographs Conservation of DC

42nd Annual Meeting – Photographic Materials, May 30, "Fototeca Pedro Guerra: Conservation of the Photographic Archives" by Cinthya Cruz

The archives of Pedro Guerra are part of the Universidad Autónoma de Yucatán in Mérida, where the climate is hot and humid. Photographic prints and negatives in this collection include many photographic processes and materials, from albumen and silver gelatin to glass plates and nitrate negatives. The goals of the photo archives are to stabilize the existing materials, catalog and organize the objects, and monitor and maintain a safe environment. Condition issues affecting the collection include broken and scratched glass, finger prints, sticky emulsion, and fungus. Nitrate negatives are immediately placed in frozen storage in Marvelseal bags after they are treated and scanned. Object codes and registration numbers specific to the archive are written on the exteriors of the bags so negatives can be located when necessary. Enclosures for other photographic materials, such as sink mats for broken plates and acid-free paper envelopes for photographic prints, also contain object codes and registration numbers. The object codes refer to the subject matter contained in the photographic image and the type of object.
 
Summary by Greta Glaser, Owner of Photographs Conservation of DC

42nd Annual Meeting — Book and Paper Session, May 30, "The Conservation of Tiffany Studio Drawings: Finding New Ways to Reconstruct Complex Paper Loss," by Marina Ruiz Molina

Two of the motifs in the book and paper presentations and posters this year were 1) paper pulp, for example in Debra Evans and Victoria Binder’s poster “Pulp Addiction: The Use of Dry Cast Pulp,” and Renate Mesmer and Jennifer Evers’ poster “Cast Paper Pulp,” and 2) flood and mold damage, which were represented in Katherine Kelly and Anna Friedman’s presentation “Conserving the Iraqi Jewish Archive for Digitization” and Fernanda Mokdessi Auada’s “Salvage of Paper Materials from the Flooding of Saõ Luiz do Paraitinga.” Marina Ruiz Molina’s presentation united these themes, in using paper pulp to conserve mold damaged items.
Marina Ruiz Molina’s case study objects were part of a collection of drawings used as guides in the Louis Comfort Tiffany studio in manufacturing stained glass. The firm went out of business in 1924, and the drawings were later found in an attic room of a marble dealer in Long Island. The collection entered the Metropolitan Museum of Art in the 1960s but they have been inaccessible due to their extensive mold damage from water damage, as seen in this combined before and after treatment picture.

Before (top) and After (bottom) of mold-damaged Tiffany drawing
Before (top) and after (bottom) pulp infill and overlay of mold-damaged Tiffany studio drawing

Marina Ruiz Molina gave a quick overview of mold and what it does to paper, causing both structural weakening and aesthetic damage from the pigments it produces. She then presented three case studies of the use of cast paper pulp. The Tiffany drawings had been executed on illustration board that was made of imported Whatman paper adhered to local wood-pulp board. She first mechanically reduced the mold by cleaning with suction under the microscope, followed by application of solvents, enzymes and chelating agents in an attempt to reduce the stain.
The paper was still stained and extremely weak. The weakness of the original paper made it especially important to match the strength and expansion properties of the infill to the original paper. Marina Ruiz Molina achieved this by mixing cotton and flax to get the right hydrophilicity and using pre-dyed reactive dye pulp to achieve the right color. She is still experimenting with pigments, but the dyes were much easier to work with. She beats the pulp with a Vita-pro3 Vitamix blender, using the blending time to control the properties. She has found that any blend time under about 30 minutes still gives good fiber length.
Once the pulp is prepared, she pours it onto a Hollytex screen (the 0.0029” Hollytex is an ideal weight). She taps the fibers with a brush to distribute the fibers and then lifts the whole screen onto blotters. For the first case study, she cast two sheets, one as an infill and one as an overlay. To adhere them she humidified the object along with the infill and sprayed the infill with a dilute methyl cellulose solution, aligning it over the drawing on the suction table.
In the second case study, the decision was made to leave the drawing on its illustration board and to mechanically remove only the damaged part of the board, cutting it away in a stepped pattern to give a better surface for infilling. Marina Ruiz Molina then adhered several layers of Richard de Bas paper to build up the inner layers, using methyl cellulose. The outer visible layers were cast paper fills.
The third case study had thin lines on the recto traveling into the mold damaged area. Marina Ruiz Molina showed pictures of casting the overlay with holes in it so the design is still visible.
Marina Ruiz Molina is still refining the technique and would like to compare dyed pulps and pigmented pulps with a microfadeometer, investigate the quantitative effects of different blending and drying techniques, and find more sustainable methods for cast paper fills.

42nd Annual Meeting – Photographic Materials Group, May 31, “Comparative Study of Handheld Reflectance Spectrophotometers” by Katie Sanderson

Katie Sanderson, Assistant Conservator of Photographs at the Metropolitan Museum of Art (MMA), presented a most informative comparative study of handheld spectrophotometers undertaken at MMA. When the Department of Photograph Conservation decided to replace its existing handheld spectrophotometer—an X-Rite 968—Sanderson along with Scott Geffert, Senior Imaging Systems Manager, researched current units available to determine the best replacement and variation in measurements taken by each.
Sanderson began by outlining the factors to consider when replacing a spectrophotometer: data continuity (extant data over 20 years); instrument agreement; data translation; software compatibility with previous and future instruments; and longevity and support (the previous spectrophotometer is no longer supported by X-Rite but still takes good data readings). In total, seven spectrophotometers—four by X-Rite and three by Konica Minolta—were tested against the MMA’s X-Rite 968 and a bench-top spectrophotometer equipped with an external remote diffuse reflectance accessory probe in the Department of Scientific Research. The seven spectrophotometers examined were:

  • X-Rite 964
  • X-Rite eXact
  • X-Rite Ci64
  • X-Rite RM200
  • Konica Minolta 2600D
  • Konica Minolta 2500c
  • Konica Minolta FD-7

Before delving into the specific finding of each unit tested, Sanderson provided a brief overview of how spectrophotometers work. She explained that an object is illuminated by a light source of a specific spectral range, a detector collects any reflected light, and a unique spectrum is produced. While some light sources extend into the ultraviolet region of the electromagnetic spectrum, most are within the range of visible light (400-700nm). The two most common geometries for spectrophotometers are 0/45—in which the first number represents the angle (in degrees) of the light source and the second number the angle of the detector—and integrated spherical.
As Sanderson described, some of the units tested had an integrated spherical geometry that takes into account specular reflectance; these spectrophotometers can be operated in either specular component excluded (SCE) or specular component included (SCI) mode. The aperture of the X-Rite units was set to 4mm—that of MMA’s current spectrophotometer—andthe Konica Minolta units were set to 8mm as they exhibited a range of apertures and, in some cases, were not adjustable.

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X-Rite Digital SG ColorChecker. Image courtesy of X-Rite

 
To determine an appropriate replacement, several reference standards and sample objects were tested with the seven spectrophotometers. The reference standards tested were obtained directly from X-Rite that is about to release a new Digital SG ColorChecker. The new target will include the same colors as the existing one but will utilize new pigments for some colors. For this comparative study, MMA obtained samples of the new standards to assemble its own large-format color checker. Ceramic BCRA calibrationcolor tiles were also tested as well as objects with varied surface qualities—chromogenic photographic prints (glossy and matte), watercolorpaper, textiles, and paintings. Five readings were taken and averaged for each spot tested; the units were lifted and repositioned before each measurement to account for a margin of error in positioning when monitoring color shift in objects over time using a spectrophotometer. Mylar® templates were created to facilitate positioning of the meters. All testing was completed by a single operator and resulted in approximately 12,000 readings!
To evaluate the variation in measurement between spectrophotometers, MMA’s X-Rite 968 was used as a master and delta E values were calculated for each of the 140 X-Rite color references. Sanderson summarized the results of this comparative study as follows. Meters with a 0/45 geometry produced readings with the closest match to the unit currently in use, which was not surprising as both are 0/45 instruments. When operated in SCE mode to exclude specular reflectance, the integrated spherical instruments fared worse than the 0/45. The easiest-to-use instruments were lightweight with built-in crosshair targets to facilitate alignment with a template. Finally, Sanderson introduced the concept of acceptable tolerance meaning that the operator should simplify the use of spectrophotometric readings by using a single instrument with a single set of standards. During the Q&A session that followed this presentation, a member of the audience asked which spectrophotometer MMA ultimately selected.   Sanderson responded that the X-Rite eXact was selected for several reasons: it is lightweight; it produces data reasonably consistent with MMA’s existing spectrophotometer (understanding that data translation will be necessary regardless of which instrument is chosen); and long-term support from the manufacturer as well as continuity in data and software.
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X-Rite eXact spectrophotometer. Image courtesy of X-Rite

 
The presentation concluded with a discussion of areas of further research within this project, specifically continued analysis of data pertaining to the UV-radiation source found in some of the meters as well as the use of SCE settings in spherical integrated systems for more highly textured surfaces like those found in textile objects. Finally, it is a goal of MMA to complete processing of all data collected during this study and make it available to a wider audience so that it might contribute to more standardized color communication within the field of conservation and allied professions.

42nd Annual Meeting – Photographic Materials Group, May 31, “Characterization of a Surface Tarnish Found on Daguerreotypes under Shortwave Ultraviolet Radiation” by Krista Lough

Krista Lough, graduate intern in photograph conservation at the Metropolitan Museum of Art and third-year student in the Buffalo State College (BSC) program in art conservation, presented an interesting talk on the presence and potential sources a particular fluorescent tarnish found on many daguerreotypes when viewed under shortwave ultraviolet radiation. In addition to examination and photodocumentation of a set of daguerreotypes that exhibit this type of fluorescence, Lough also used Raman spectroscopy, scanning electron microscopy (SEM), and x-ray diffraction (XRD) to determine that the fluorescent tarnish is copper- and cyanide-based.
The presentation began with a summary of prior research on this subject by Lee Ann Daffner, Dan Kushel, John Messinger, and Claire Buzit Tagni. These studies corroborated Lough’s findings in characterizing the fluorescent tarnish as copper- and cyanide-based. These studies also showed that the tarnish was either removed or its fluorescence quenched when the daguerreotypes were treated with ammonium hydroxide.

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Daguerreotype and brass mat from study observed normal illumination (top) and UVC (bottom) to reveal fluorescent tarnish. Image courtesy of Krista Lough

 
Following a brief review of the phenomenon of fluorescence and its causes, Lough presented the photodocumentation of nine daguerreotypes that were examined during this study. The plates came from two sources—a private collection and a study collection at Buffalo State College—and only those from previously opened packages were examined. Lough’s research focused on determining the source of the fluorescent tarnish and its long-term effects. While the plates varied widely in condition, three primary types of fluorescent tarnish were identified: edge tarnish; rings and circles; and continuous film. The characteristic fluorescence was only observed when the plates were viewed under shortwave UV-C and not under longer wavelengths of ultraviolet radiation. Lough also noted that it was not always possible to associate fluorescent areas with tarnish perceived under visible light. Further, the greenish fluorescence was observed on the verso of some of the plates and along the verso and beveled edges and brass mats that accompanied some of the daguerreotypes. No strong connections could be made, however, between the fluorescence observed on the plates and the corresponding components of their once-sealed packages.
As part of her research methodology, Lough created a number of pure copper and silver-coated copper mock-ups. The mock-ups were treated with both potassium cyanide and sodium cyanide in an attempt to produce the same fluorescent tarnish observed in the 19th-century daguerreotypes. Ultimately, the tarnish only formed in the mock-ups treated with sodium cyanide in areas of exposed, pure copper. The fluorescent tarnish did not form on the plates treated with potassium cyanide or where the copper mock-ups were protected by a coating of silver.
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Mock-ups observed under normal illumination (left) and UVC (right). Image courtesy of Krista Lough

 
To characterize the composition of tarnish, the mock-ups and select 19th-century daguerreotypes were analyzed using Raman spectroscopy, SEM, and XRD. The Raman spectra obtained indicate that the composition of the tarnish was identical in all spots analyzed. SEM was used to create elemental maps of some of the tarnished areas on one of the 19th-century daguerreotypes. A higher concentration of copper, carbon, and nitrogen and a lower concentration of silver were revealed in the areas of tarnish analyzed. Further, a higher concentration of sodium was observed in the areas surrounding the tarnish spots, perhaps an indication of previous treatment with sodium cyanide. Finally, XRD analysis of the fluorescent tarnish on the historic plate produced peaks for silver sulfide and pure silver. Unfortunately, while cyanide was identified on one of the mock-up plates, it was not found on the historic daguerreotype examined and it is thought that the quantities present may be below the detection limits of the XRD instrument.
Lough concluded the presentation with a list of daguerreotype procedures documented in historic literature that could account for the presence of cyanide: electroplating, cleaning, brightening, fixing, gilding, and engraving by galvanism. She also identified avenues for future research including investigation into whether or not the tarnish should be removed, the presence of copper cyanide on brass mats, and potential problems or affects to the daguerreotype that may arise if the tarnish remains untreated. Lough suggested documentation of the fluorescent tarnish could be used to develop a monitoring program for daguerreotype collections and potentially map trends during the examination of larger collections to determine, for instance, if a specific cyanide procedure is common to daguerreotypes from a particular period or location. In closing, Lough summarized the findings of her study in three main points: UV-C examination is a useful tool for understanding the condition of daguerreotypes; the fluorescent tarnish was positively identified as copper cyanide; and the objects exhibiting this characteristic fluorescent tarnish should be handled with caution as the tarnish is toxic.
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The copper cyanide tarnish is toxic! Image courtesy of Krista Lough

 

42nd Annual Meeting – Photographic Materials Session, May 30, “Preserving Ernest Hemingway’s Photograph Albums and Scrapbooks at the Finca Vigía,” by Monique Fischer and M. P. Bogan

Finca Vigía, Ernest Hemingway’s Cuban home from 1939 to 1960, is open to the public and situated at the top of a windy hill with tropical conditions and occasional hurricanes. It holds not only much of the original furnishing from the time of Hemingway’s residence, but also a large part of Hemingway’s personal library and archive, including manuscripts, letters, over 3000 photographs, scrapbooks, photograph albums, art collections, maps and a 9000 volume library.
Preservation at the Finca Vigía is a balancing act. For instance, the staff tries to mitigate some of the heat and humidity by closing doors and blinds, but this disappoints people who have made the pilgrimage to Hemingway’s house, only to find they cannot look inside. The current director of the house wants to “preserve the soul of Hemingway,” presenting the house as much as possible as if Hemingway might still be living there. This means that many intermediary measures for protecting the objects, such as removing the objects altogether from their environment, are often not options.
NEDCC (the Northeast Document Conservation Center) has been working with Finca Vigía for over ten years. They began with a preservation assessment, followed by a condition assessment of the book and paper materials. Conservators from NEDCC visit Cuba for one week every six months. They can bring only the materials they will use—no extra—so treatment and rehousing need to be carefully estimated and planned. The NEDCC’s role in this partnership is to provide training and advice.
Finca Vigía’s paper conservator, Néstor Álvarez Gárciga, carries out treatment, with the assistance of interns and conservation assistants. The conservation space is two small rooms, one under the kitchen. Electricity can be shut off without warning, and running water can be in short supply.
Once M.P. Bogan had laid out the context and obstacles of conservation at Finca Vigia, Monique Fischer then described individual treatments for four volumes surrounding Hemingway’s 1954 Nobel Prize for Old Man and the Sea and the subsequent movie production. She first addressed the treatment of a storyboard book for the movie the Old Man and the Sea. It is a volume of diazotypes with gouache hand-coloring. Her research found that storyboard books were sometimes distributed as thank you presents to individuals involved in the making of films, but both the extent of the hand-coloring and her attempts to find similar albums suggest that this may have been a unique gift to Hemingway. There was mold-bloom visible on the volume’s binder, and the gouache was found to be very water soluble. In this treatment there was a delicate balance between caring for the physical stability of the materials and keeping the book as close to its original state as possible. In the end, the binder and the diazotypes were surface cleaned. The curator made the “uncomfortable decision” to allow the conservator to remove the diazotypes to storage, digitize them and place copies in the book in their place. (See the following day’s presentation on environmental concerns for the exhibition of diazotypes).
The next album discussed was the photograph album Homenaje Nacional (national tribute), which is on permanent display. The photos are spot-adhered onto pages that are held together in a post-bound album. The album was treated through removing the photos, washing, digitizing, reassembling with new screw posts, and will be put back on permanent display. Treatment was complicated by the lack of both a consistent source of pure running water and the amount of blotter that a typical U.S. conservator might go through in washing a volume. While the Finca Vigía may lack pure running water and a sink in the conservation lab, it has plenty of moisture in the air, and Néstor Álvarez Gárciga used the water gathered by the dehumidifiers, working in a tray outside, where the light was good. Néstor Álvarez Gárciga also used the star of this year’s Book and Paper Group Tips Session—Tek-wipe—as an absorbent and washable alternative to blotter.
For the volume of congratulatory telegrams, a different approach was taken, as the fragile telegrams were considered the most important original part of the album. The album was disassembled, removing the telegrams and the paste downs, and reassembled onto Permalife paper. The album was then placed into a 3-flap wrapper.
The most complicated treatment of the four was the Recuerdo 1956, also known as the fishnet album, after the fishnet wrapped around its cover. It was made by Hemingway’s wife Mary Welsh, and included the full gamut of album problems, such as colored pages, detaching pages, and newspaper clippings, photographs and even some film strips, many of which were attached with rubber cement and tape. The items were removed and the adhesive locally reduced as much as possible with acetone and ethanol. The pages were all washed and guarded with toned Japanese paper and then the items spot adhered in their original places. During conservation the volume was also digitized. One unusual feature of the album was its inclusion of film strips. These were removed from the cardboard mounts, and Néstor Álvarez Gárciga used the film sprockets as places to put Mylar clips so that the film strips can now be picked up and properly viewed with transmitted light without touching the film itself.
This talk presented the difficult balance between caring for the items as physical objects and allowing the public a glimpse into Hemingway’s home life and the items that surrounded him. Néstor Álvarez Gárciga and the NEDCC team have shown what can be achieved even in the face of formidable obstacles.