Specialty Sessions – Page 13 – AIC Blog Archives: Conservators Converse

AIC 44th Annual Meeting, Book and Paper Session, May 17th, 2016: Post-flood Development of Mass Treatments at the National Library of Florence: The Roots of Library Conservation

Sheila Waters is the widow of Peter Waters, former Conservation Officer and Chief of the Conservation Division at the Library of Congress, and as such she became intimately connected with the conservation world, and more specifically that of library conservation. Ms. Waters’ talk at AIC’s 44th Annual Meeting in Montreal, Quebec, focused on describing how the profession of book conservation originated in the mud of Florence, where the Biblioteca Nazionale Centrale di Firence (BNCF) had been inundated by the flood waters of the Arno River in November 1966.
In November 1966 the Arno River, which runs through the heart of Florence, burst its banks and flooded the BNCF. Books had been stored in the basement in 1944 during World War II and had not been removed. Peter, having a reputation for being an innovative binder after collaborating with Roger Powell on the Book of Kells, was contacted by the British Library’s Howard Nixon, who had been contacted by the director of the BNCF, Dr. Emanuel Casamassima. Told to take two other colleagues and depart for Florence immediately, Peter Waters chose Tony Cains and Dorothy Cumpstey to be his seconds and set up a staging area at the Forte Belvedere for the damaged books. Below on the map, the location of the BNCF and of Forte Belvedere are circled. The Forte is quite a bit higher in elevation, which explains why it was chosen as an initial staging location.

When Peter arrived in Florence, students were still removing muddy and damaged books from the BNCF. At the Forte, he witnessed the extent of the damage: vellum pages had rotted, and the books were defaced with mud and sawdust. Limp vellum bindings had withstood the onslaught of the flood the best, however, an observation that would have a profound impact on conservation.
Tony Cain and Chris Clarkson took over salvage at the Forte, while Don Etherington took over at the BNCF, where Peter decided to stage future cleaning and triage efforts.
Sheila, an accomplished calligrapher and designer, helped Peter develop a triage “card” in both English and Italian that would help those involved in the recovery effort decide what to do. If a book was labeled “Okay,” for example, it could be handled by a student, but a “STOP” sign indicated that it needed treatment by a specialist.
Benches were installed in the main reading room of the BNCF where books were mended and bound by as many as 30 workers at one time. Starting in September 1967, smaller books began to be rebound in limp vellum, as this binding style was found to be long-lasting, fairly quick to make, and strong. The workers at the BNCF and the Forte cleaned, deacidified, and resized the paper; took pH measurements; and performed on-the-spot chemical analysis when necessary. Heat-set tissue was derived as a means for mending torn paper. As the years went by and the damaged volumes were treated and rebound, the conservation space at the BNCF was moved downstairs into the basement of the library, and the number of staff grew smaller. Today there are only a few employees, compared to the 30 employed there immediately after the flood.
Peter Waters was called to help Florence in a time of crisis in November 1966, but it is clear 50 years later, in 2016, that the innovations and procedures that he and his team implemented during the response to the Florence Flood have formed the structure of many basic tenets of library conservation.

Sheila’s talk was a condensed version of her book “Waters Rising: Letters from Florence,” published by The Legacy Press, which contains the letters that the spouses exchanged with one another while Peter was in Florence. Julian Waters, one of Sheila and Peter’s sons, accompanied his mother on the podium and read excerpts of Peter’s letters to Sheila since “he sounds like his father.”

In honor of the 50th anniversary of the flood, there will be a symposium at the University of Michigan on November 3-4, 2016. Attendance is free, but registration is required.

See below for a few links regarding the Florence Flood.
Peter Waters Obituary, NYTimes 2003
30 Years After the Flood, NYTimes 1997

Florence submerged: the flood of November 4, 1966

44th Annual Meeting- Joint Photographic Materials + Research and Technical Studies Session- Surface Roughness, Appearance and Identification of AGFA-Gevaert Photograph Samples- by Dr. W. Wei and Sanneke Stigter

Having encountered some very bizarre textures in matte Gevaluxe prints during a National Portrait Gallery internship several years ago, I was eager to learn more about the characterization of these interesting papers. The popular Gevaluxe papers (made by Belgian company Gevaert) often had a velvety matte appearance that was desired by many mid-twentieth century photographers.
This project was inspired by a concern that the increasing reliance of museums on digital surrogates for original photographs might not capture all of the original properties of the photograph. Even where a traditional silver-gelatin or chromogenic photograph has been used as a surrogate, the textured surface of the replacement paper might not match the original. The work Hoe Hoeker Hoe Platter by Dutch artist Ger Van Elk was used as an example of a mixed media photographic work where texture played an important role in conservation decisions. Texture can influence the perception of color, so it was important to characterize the essential properties of the paper’s texture.
Paul Messier’s research was considered an important first step, but Bill Wei’s research team in the Netherlands sought to leverage some of the technology from other industries where surface texture and roughness are systematically quantified (such as the auto industry). First, Wei gave an overview of some of the techniques employed in texture measurement: polynomial texture mapping and confocal white light profilometry. In this project, confocal white light profilometry was used to create a non-contact contour map with a resolution of 60 nanometers. Gloss measurements were also used; on a matte surface the difference between incident and reflected light is the light scattered, so the glossiness (or lack thereof) can be quantified.
The study compared human perception with quantitative texture measurements in observations of textured paper and their apparent roughness or smoothness. An Agfa-Gevaert sample book from the 1970’s served as the source material. Only three of the samples were color papers, so they were more difficult to evaluate. The 25 samples were categorized into 5 groups. Some of the groups had a “macro” texture of waviness, versus a “micro” texture of roughness on a much smaller scale. Group 1 was smooth. Group 2 papers had a very fine texture. Papers assigned to Group 3 displayed the fine texturing in the Group 2 papers, combined with a large-scale waviness. Group 4 exhibited the waviness of Group 3, without the fine texture. Group 5, which included some of the color papers, was comprised of a very regular pattern of raised circular nubs or dots. For anyone who has a lot of family photos from the 1970’s, that dot texture will seem quite familiar.
The research is ongoing, so the presenter mentioned some preliminary observations, without drawing any conclusions. There was not a direct relationship between roughness and gloss. For example, samples from Groups 4 and 5 were just behind group 1 in gloss. The human observers demonstrated that their perceptions of smoothness did not always correlate with the quantitative measurements, especially for some papers in Group 2. It will be interesting to hear the follow-up results as the research team continues the project.

44th Annual Meeting – Emergency Session, May 16, “Lighting a Fire: Initiating an Emergency Management Program,” by Rebecca Fifield

Instituting an emergency management program at your organization is hard. I don’t think anyone would ever argue that. And it’s not just about a written emergency plan. While this is a great place to start, and certainly integral to a complete program, it doesn’t inspire and excite. It doesn’t create an emergency preparedness culture. Rebecca Fifield, a Preservation Consultant and owner of Rebecca Fifield Preservation Services, spoke about several ways to ignite a planning effort and maintain momentum when starting an emergency management program at your institution.
First, create a vision. Don’t just update your phone tree. Get a budget line, meet with your local community, and set up training exercises. Asking for a premium plan built on best practices creates the greatest impact and helps staff get behind the change.
Next, refine and strengthen that vision by creating relationships with allies. Allies can make your project stronger by challenging assumptions, informing the project with their industry expertise, and using their connections to develop momentum around your idea. But how do we identify these allies? Are they our supervisors? Yes! If they haven’t considered it before now, educate your supervisor about how risk management and emergency preparedness go hand-in-hand and how they both are part of our professional responsibility. (See Marie Malaro’s A Legal Primer for Managing Museum Collections). Are our allies Conservators, Registrars, Collections Managers, Security, Facilities Managers, Curators, Educators, IT staff, Human Resources, Communications, and Development? YES TO ALL! Emergency preparedness efforts can often be attached to efforts such as the institutional audit process, health and safety initiatives, construction, or large-scale conservation projects. Start a talking campaign. Remember that a disaster effects every staff member, so it only makes sense to have them as part of your web of allies.
Set a time-sensitive goal. Put a time frame on preparedness to create a challenge, because it can be easy to keep putting off planning. Pose questions that reveal preparedness needs for specific institutional goals: Could there be a potential protest related to an upcoming exhibition? Will you be effected by the upcoming hurricane season? Are you in a region that often deals with large amounts of snow? Look at your historical record. Has your organization suffered a past emergency, and what was the impact on people and collections? Are you dealing with aging infrastructure? Survey your staff. Does everyone know their role in an emergency? These aren’t meant to be scare tactics. This is to make sure that the decision-makers at your institution are well-informed.
Connect with other institutions and your community. Reach out to similar organizations to your own and find out who’s on their planning team and their responsibilities. Take this time to establish an informational exchange. Meet other emergency managers in your region. Get involved with professional organizations such as Alliance for Response, as well as regional responders like the Virginia Association of Museum’s Emergency Response Teams and your local Community Emergency Response Team (CERT). Encourage involvement from staff by having some of these organizations come to you for a talk or training exercises.
Be resilient in the face of negativity. We are all very busy and you may receive some push-back from management and staff. Use emergency management as an opportunity for situational leadership, which allows you to display your ability to lead for the future. It hones your persuasion skills, creates ties with operations and administration colleagues, and provides you with a ready opportunity for development that your current position may not provide. It may take months, and even years, to understand how your institution will function in an emergency, the decisions that will need to be made, and the conversations to confirm direction and readiness. Just remember, that time is as important as developing the plan itself.

Joint 44th Annual AIC Meeting & 42nd CAC-ACCR Annual Conference, Art on Paper Discussion Group, May 17th

When I attended this session, I was not planning to blog about it. Yesterday, I saw that no one had signed up to write about this, so I figured I would share the notes I have with the larger community.
Peggy Ellis began discussion with her rousing talk entitled Paper is Part of the Picture. (To envelop the room in the scent of old paper as she spoke, she passed around a bottle of Paper Passion Perfume.)
She feels that there seems to be a curious lack of language to describe paper. Often, no mention is made of the paper itself in the literature of art. It is important to be able to describe the physical properties of paper, even those that have been common in our lives. Common papers may change with technology and not be familiar to those in the future. For example, nineteenth century writing paper and etching paper had specific qualities that contemporaries would have recognized. In the past, artists were particularly attuned to the qualities of paper. Today, preference is given to extremely white paper. Most of today’s common papers are meant to travel through a printer.
She ended with a call to action: Using as many of our senses as we can, paper conservators need to develop and standardize descriptions that enable a fuller understanding of paper.
Kristi Dahm’s talk was entitled Winslow Homer’s Engagement of the Materiality of Paper.
Homer is an example of someone who was very attuned to paper and was very particular when choosing paper. He chose the best paper for the technique he intended to employ. Allowing the paper to show through is an important component of his and many other watercolor paintings. When the paper changes in appearance with age, the art is changed.
Homer often used watercolor blocks. You can find evidence of this, such as brown lines of adhesive at the edges, or white voids where adhesive was removed.
He used a particular paper during a trip to Bermuda in 1888/89 which has deep, diagonal furrows on the verso. In some cases, his printer printed his plates on both paper and parchement. The parchment versions were mre expensive.
He sometimes used Japanese vellum, which was introduced to Paris in 1888 and became very popular with artists. It was a smooth, dense Japanese paper with a lustrous, calenared surface. There were European-made imitations.
There are some posthumous impressions of Homer prints that were created by his later printer using the same paper, so they are hard to tell from originals.
The third talk, entitled Connoissership and Conservators’ Practice, was by Marian Dirda. She spoke about the importance of understanding the qualities of hte paper to inform treatment decisions.
Every institution has a curatorial tradition on which some of those decisions are based. This comes from an understanding of the part that the paper plays in conveying the spirit of the artwork.
For example, washing and flattening should not be done on a Mary Csssatt because undulations are typical in her prints and should be left. If something is an extremely rare first state, you should not wash it because it is important not to loose any characteristics. You can learn by comparing copies and variations of the same print.
Papers from the 1960s and 1970s are particualrly vulnerable to oxidative attack. The quality of paper has rise since the 1980s. We don’t have a lightfastness stadard for paper like we do for media.
Amy Hughes rounded out the presentations with a follow up to her talk about gels in paper conservation. To measure pH and conductivity, she uses a biopsy punch to make a small agarose pellet She leaves it on the paper 5 minutes, then places it in the conductivity meter first, then places it in the pH meter with 2 drops of water. The paper is less altered when you match the paper’s conductivity with that of the treatment solution.
She makes a bunch of stock solutions that will keep for a few months in the fridge. Learning to make the stock solutions is complicated. You need an instructor to teach you. There will be some future workshops with Amy, Daria Keynan, and/or Chris Stavroudis.
These presentations were followed by a lively discussion. Here are some select points:
* More study is needed about why color shift is happening in paper.
* It is important to collaborate with paper historians.
* There may or may not still be copies available of the Print Council of America Paper Sample book. Get one if you can. (I did a quick search and did not see any listed for sale online.)
* We need to create something even more comprehensive than that book.
* Colors can be scientifically measured, but simple color words and modifiers may be more useful.
* In a treatment report, it is always good provide context for why a treatment path was chosen.
* When concerned about over lightening, one trick is to light bleach from the back.
* Is it helping paper chemistry to preserve paper tone? We are not necessarliy extending the paper’s lifetime by washing.
* Why not just start with sodium borohydride? Paper chemists believe it is actually good for the paper.
* National Gallery of Art is putting together a comprehesive paper library. Please contact Marian Dirda if you have dated, known samples.
* Look, look, look, and look again!

44th Annual Meeting – Book and Paper, May 16: “Watercolor Pencils: Composition and Conservation Concerns,” presented by Lauren Buttle and Natasa Krsmanovic

It always amazes me how much we have still to learn about various types of media. The presentation by Lauren Buttle and Natasa Krsmanovic underscored how little we still know about watercolor pencils (also known as aquarelle or water soluble pencils).

Water color pencils first appeared during the 1920s, with Staedtler being the first to mention them in 1928. They are related to copy pencils, which contain a water soluble dye and were introduced in the late nineteenth century.
In their study, Lauren and Natasa and their coauthors, Laura Hashimoto, Michael Doutre, Kaslyne O’Connor and Rosaleen Hill, examined four products: Reeves watercolor pencils, Staedtler karat aquarelle 125, Staedtler ergosoft aquarelle, and Derwent watercolor pencils. These were first analyzed using mid-IR spectroscopy, which revealed that each of the products had the same general composition. All contained clay, water-soluble wax, a polysaccharide binder, and colorants. The wax was further revealed to be a modified polyethylene glycol, or mPEG.
The second phase of the project involved testing samples to determine the impact of conservation treatments and solvents. The researchers drew lines with watercolor pencils onto Windsor & Newton watercolor pen and ink paper that was subsequently cut into 14 sets of inch-long strips. They tested four colors – red, blue, grey, and black – for each product. Of 14 watercolor pencil test strips, seven were stored in the dark (that is, they were not aged), while seven were artificially aged at 95°C and 50% RH for 96 hours. They were then tested for reactivity with water, ethanol, acetone, and toluene immersion for 5 minutes each, non-contact exposure to 100% RH for an hour, and smudging with a smudge stick, with additional samples retained as controls. Color change was measured with a Minolta chromometer, with readings taken thrice for each testing area.

Red watercolor pencil was most sensitive to immersion

Their results showed that exposing watercolor pencils to wet treatments is exactly as problematic as one might assume. Aged and unaged samples both experienced significant bleeding when immersed, particularly undergoing aqueous immersion. Of all colors, red had the most dramatic response to immersion. Immersion treatments also resulted in color shifts, with polar solvents causing greater shifts in color than non-polar solvents. However, some of the color change was due to change in the color of the paper.
Humidification appeared to have no effect; however, the researchers did not dry the paper under pressure, and it is possible that there may have been some off-set of color if they had done so. All media was affected by mechanical smudging, although aged media was affected to a smaller degree.
This talk raised a lot of interesting questions, and the discussion following the presentation suggested avenues for further research. One attendee asked when mPEG was introduced, raising the idea that the composition of these pencils has likely changed over time, while others suggested testing the solubility of colors in xylene, or testing the pencil lead directly. This research will be continuing at Queens University, and I am excited to see where it will lead.
Author’s Note: The original version of this blogpost omitted the names of Michael Doutre and Kaslyne O’Connor. The author apologizes for the omission.

44th Annual AIC meeting, May 17, 2016, “An Unexpected Surface: Research and treatment of a 19th century mounted oyster shell by Froment-Meurice” by Emily Brown

This talk focused on the research and treatment of Froment-Meurice oyster shell artifact made by Emile Froment-Meurice. The conservation concerns were identification of the corrosion layers and treatment of the metal surfaces. The artifact was purchased by William Walters in 1878. It is a composite artifact that depicts two putti discovering a pearl inside of an oyster. The oyster shell holds a natural pearl in a metal mount. The mermaid stem and putti are a silver copper alloy, the base is silver with a gold enriched surface and the hinge is a gold alloy. The oyster shell artifact was damaged and repaired multiple times in the past. The 1930 photograph from the museum shows the object in one piece.
The main condition issue for this treatment was the heavily tarnished metal surfaces. The silver and gold elements were nearly black with heavy tarnish overall. In the 1840s the goldsmiths would often intentionally create a darkened oxidized surface on silver. In a 2003 French catalogue “Tresors D’Argent” (translated as “Silver Treasures”) two similar shell objects are included, but both have polished and shiny metal elements. Other artifacts are listed as “oxidized silver and painted sheet metal” objects. A similar oxidized silver surface can be found on the commemorative shield (c. 1881) by Froment-Meurice in the Art Institute of Chicago labeled as “an elliptical shield of oxidized silver”.
There are a few differences between tarnished silver and oxidized silver. Tarnished silver is an unintentional patina created by airborne pollutants. Oxidized silver is an intentional antiqued patination created by chemical compounds. The small traces of silver chloride found on the surface of the artifacts may be a byproduct of silver chloride that was used to antique the surface of silver objects. With this in mind, the decision was made to clean the silver, but not remove the black surface. The gold elements would be cleaned until bright.
The gold and gilt silver components could not be cleaned with abrasion or normal polishing. Instead an acidified thiourea xantham gum gel was used to clean the surface. The gel as applied with a cotton pad and rinsed with water. The dwell time was kept to a quick 5 – 10 seconds. The process was repeated as needed. For the metal clasp, mylar was placed between the metal and the shell to protect the surface of the shell. The gel was applied with a brush and then rinsed with the use of chem-wipes and a bristle brush. The gel cleaning produced a bright and shiny surface. The process had excellent control and a quick removal of the material was possible. The putto were adhered into place, but the shell was left partially unassembled for transportation. A complex and well-designed storage and shipment box was created for the artifact. This storage box was featured in the STASH flash III on May 14^th and will be published on the AIC STASH website.

44th Annual AIC meeting, May 17, 2016, "When in Rome, do as the Romans do? The Conservation of an Italian Marble and Micromosaic Tabletop” by Elizabeth La Duc

Elizabeth La Duc gave an engrossing talk in the Objects Specialty session on the conservation treatment of a 19th century Pietre Dure and micromosaic tabletop belonging to the Josiah Quincy house of Historic New England. The stone tabletop, positioned on top of a painting and gilded wooden base, had and been conserved in the past. Her treatment was readdressing this past treatment and returning it to exhibit-able condition.
Pietre Dure translates into English as “hard stone”. The Pietre Dure portions consist of decorative stones set into the carved channels within the black marble base and adhered with a rosin and beeswax. The micromosaic areas are images made up from tiny tesserae called smalti. The smalti are cut to shape and inserted into an adhesive of linseed oil, lime and marble dust. The top surface was polished to a flat surface and the gaps between the tesserae were filled with tinted beeswax. This beeswax can be seen under ultraviolet light, but it has often been lost through over cleaning and use.
The table top was in poor condition. The four sections were poorly adhered and slightly misaligned. A large crack in the stone tabletop ran across the middle of the tabletop and transected both the Pietre Dure and the micromosaic elements of the table. Two stone inlays were missing and there were losses in the micromosaic along the central break.
The conservation treatment started with a surface cleaning of calcium saturated water with the pH raised to 8.5 with ammonia and added drops of Triton. Acetone was wicked into the old joins to dissolve the older restoration adhesive. B72 and microballons were used to glue the pieces back together.
For the conservation of the Pietre Dure portions two options were considered. In Florence, the missing elements would have been replaced with new cut stone. The Pietre Dure objects are decorative and require a high level of finish. Another Italian treatment option is to cast crushed stone and resin to recreate the missing inlays. This second approach was chosen and the new Pietre Dure elements were created with tinted epoxy bulked with fumed silica cast into silicone rubber molds. In some areas it was necessary to back of the Pietre Dure areas of loss with a layer of Japanese tissue coated with B72. The epoxy elements were then cast directly into the loss. Gamblin conservation colors were used to finish off the top of these fills and a layer of Acrysol WS24 was brushed on top to give a polished shine.
The micromosaic repairs were based on similar micromosaic designs. Since the micromosaics were mass produced with only a small range of designs, similar images could be used as guidelines for decorative elements on the fills. The areas of loss in the micromosaics were backed with acid free matt board topped with a layer of modostuc. Gamblin conservation colors were used to inpaint the surface in two steps. The first step painted the background colors and the second step painted the individual small tesserae.
This was an elegant and well executed treatment with results that were aesthetically pleasing and reversible. Under close examination, the areas of filled loss are distinguishable from the original material. This was a great talk and I hope to get a chance to work on micromosaics someday!

44th Annual Meeting – Objects-Wooden Artifacts Session, Monday 16 May 2016, "The study of boxwood prayer beads and miniature altars from the Thomson Collection at the Art Gallery of Ontario and the Metropolitan Museum of Art” presented by Lisa Ellis

Lisa Ellis, Conservator of Sculpture and Decorative Arts at the Art Gallery of Ontario (AGO), presented collaborative work on the study of boxwood prayer beads and miniature altars from the early 16^th century (c. 1500-1530). The beads and altars are very small, complex, and intricately carved artifacts whose construction has not been well characterized. Teams at the AGO and the Metropolitan Museum of Art (MMA) are exploring the carving techniques and joinery strategies using careful examination, micro-computed tomography (µCT scanning), and physical deconstruction of select artifacts to better understand how the pieces were created.
Because of their depth and small size, traditional photography has been inadequate to capture the various layers in focus within one image, making distance sharing and comparative work impossible. In order to better share between institutions and scholars, the AGO set out to photodocument these artifacts with high resolution images that are in focus throughout the depth of the artifact. In order to do this, they are taking a series of photos at various focal depths, then stacking the images to maintain sharpness. The image quality is profoundly improved from the old hazy images that made it impossible to understand the detail.

Workshop of Adam Dirksz, Prayer bead, AGOID.29365. Detail showing “The Coronation of the Virgin.” The Thomson Collection of European Art © Art Gallery of Ontario. — Prayer bead, AGOID.29365. Detail showing “The Coronation of the Virgin.” The Thomson Collection of European Art © Art Gallery of Ontario.

Through preliminary x-radiography, they found that the artifacts can be grouped in to two broad classes: artifacts created in simple relief and artifacts created with a complex design. The complex artifacts were then µCT scanned, revealing the multiple elements joined together. Using medical imaging software, they were able to better understand the parts and see that the beads were created in layers. With the software, the various layers could be virtually deconstructed so that each layer could be examined and stacked, as if each piece were separate. At the MMA, Pete Dandridge, Conservator and Administrator, was able to disassemble a bead to physically see the pieces, which further helped to interpret the µCT data and reinforced the understanding of the layers. Since not all artifacts can be taken apart, the µCT scans provided to be invaluable in examining the construction and documenting the process. One example showed a bead attached to a rosary that had multiple roundels set into the main structure. The roundels could be virtually removed with the µCT scans and software, revealing a numbering system beneath.

Workshop of Adam Dirksz, Prayer bead, AGOID.29365. Micro CT scan revealing use of pegs in depiction of “The Coronation of the Virgin.” The Thomson Collection of European Art © Art Gallery of Ontario. Scans courtesy of Sustainable Archaeology at Western University. — Prayer bead, AGOID.29365. Micro CT scan revealing use of pegs in depiction of “The Coronation of the Virgin.” The Thomson Collection of European Art © Art Gallery of Ontario. Scans courtesy of Sustainable Archaeology at Western University.

In addition to examining the construction, they also looked at the limited polychromy present on some beads. Although most pieces were unpainted, a few pieces had painted details in blue, black, or red. These elements, along with adhesives and coatings, are being analyzed at the MMA and the Canadian Conservation Institute (CCI) with a suite of techniques.
These artifacts and findings about them will be presented in an exhibition, Small Wonders: Gothic Boxwood Miniatures, opening in Toronto on Nov. 5, 2016. The exhibition will feature over 60 boxwood carvings from institutions and private collections across Europe and North America. Following its debut at the AGO, the exhibition will open at the The Cloisters at The Metropolitan Museum of Art on Feb. 21, 2017, before travelling to the Rijksmuseum on June 15, 2017. For more details about the exhibition and related programming visit www.ago.net and follow #miniAGO on twitter and instagram.
For images and further details on the work being carried out at the AGO, visit this link at the CODART eZine: http://ezine.codart.nl/17/issue/45/artikel/investigating-miniature-boxwood-carving-at-the-art-gallery-of-ontario-in-toronto/?id=119#!/page/1
Investigation on these materials have been on-going. For some background on earlier work that started this process, visit this link on the AGO website: http://www.ago.net/idea-lab
Other collaborators not mentioned above include: Alexandra Suda (AGO), Andrew Nelson (Sustainable Archaeology, Western University), Barbara Drake Boehm (MMA – Cloisters), Elizabeth Moffatt (CCI – retired), Jennifer Poulin (CCI)

44th Annual Meeting – Book & Paper Session, May 17, "Targeted Cleaning of Works on Paper: Rigid Polysaccharide Gels and Conductivity-Adjusted Aqueous Solutions," Amy Hughes and Michelle Sullivan

The past few years have seen an uptick in the number of BPG session talks focusing on cross-disciplinary materials and techniques that allow for more targeted treatment approaches. Specifically, the use of rigid polysaccharide gels, such as agarose and gellan gum, and conductivity-adjusted waters are techniques with a more established history in paintings and objects conservation that are being adapted for treatment of works on paper.
Michelle Sullivan, Graduate Fellow in the Department of Paper conservation at the J. Paul Getty Museum, spoke first about the use of gel systems in targeted cleaning of works on paper. Sullivan outlined the advantages of gel systems, which include:

targeted, precise application by cutting gels to shape
restricted lateral movement, minimizing tideline formation
increased dwell time for reagents in solution and solvents
no mechanical action, protecting paper fibers
colorless, transparent/translucent gels facilitate treatment monitoring
ease of removal, virtually no residues

While the science behind these gel systems is best left to the experts in the postprints, here are a few notes worth keeping in mind when designing treatments with gels:

Agarose is more opaque than gellan gum; gellan gum’s translucency allows you to more closely monitor treatment.
Casting thinner gels affords greater control over solvent diffusion.
Pore size is inversely related to concentration; the higher the concentration, the smaller the pore size, which leads to greater capillary action.
You can use a range of modified aqueous solutions with the gel systems, including pH- and conductivity-adjusted waters, chelators, and enzymes.
The gels can be used with polar solvents; just soak the prepared gel in solvent of choice overnight. Sullivan noted that the gels become more rigid when soaked in solvent, so she recommends cutting them to the desired shape and size prior to soaking.
Examination under UV revealed more consistent washing with the gel than with a traditional blotter wash.

Sullivan then presented two case studies. First, by tracing the outline of a stain onto a sheet of polyester film and then using this template to shape the gellan gum, she was able to reduce the stain locally without the risk of tidelines. In the second example, Sullivan humidified a print and then washed it overall by placing it face-up on a sheet of gellan gum. A medium-weight sekishu paper was placed between the print and the gel. (She tried Hollytex as a washing support, but it did not allow for consistent penetration.)
Experimentation is currently underway to determine whether or not gel residue is left behind on the paper substrate. Agarose, gellan gum, and methylcellulose are being tagged with UV-fluorescent dyes in order to track their movement onto the paper; results of this testing should be available in 2017.
Next, Amy Hughes, Andrew W. Mellon Fellow at The Metropolitan Museum of Art, spoke about her research into the use of pH- and conductivity-adjusted waters in treatment. Adjusted waters minimize swelling of the paper fibers while at the same time improving wetability and solubilization of degradation products, allowing conservators to design treatments that are more sensitive to the object. Again, I’ll leave the scientific explanation to the expert (though I have to note her lovely illustration of osmosis featuring a very plump carrot), but the procedure involves measuring surface pH- and conductivity of the object using agarose plugs and handheld meters (this video from the Getty clearly outlines the process) and then combining ammonium hydroxide (weak base) and acetic acid (weak acid) to form ammonium acetate (neutral salt) that, with water, can be used to create an isotonic solution (a procedure also outlined in a Getty video). Hughes did note that some objects washed in adjusted waters retained a vinegar odor that took 3-5 days to dissipate; further testing is underway to address this issue.
These talks left me feeling very inspired to begin testing out these new treatment methods in my lab!

44th Annual Meeting – Research and Technical Studies, May 17, "Characterizing the Age of Ancient Egyptian Manuscripts through micro-Raman Spectroscopy" by Sarah Goler

This is another session that I tweeted (@taradkennedy), so not a long post, but enough to give you the gist at least.
Ms. Goler was using micro-Raman spectroscopy for dating of Egyptian manuscript material.This is super cool because normally we’d have to take a sample of a manuscript and do carbon dating in order to determine a date of an unknown. With this method, we don’t!
So, how does it work? Essentially measurements are taken of the carbon black ink on a particular manuscript using micro-Raman spectroscopy. Using the difference in the dominant peak heights in the spectrograph with ink samples where the date is known, ratios are plotted and graphed to show dates:

Height ratio between peaks D & G and document date ranges

So, the more plots you have, the more dates you have; and the more dates you have, the easier it is to determine the date range of an unknown manuscript.
To test that this would work, Ms. Goler analyzed a manuscript where she didn’t know the date range, but the librarian/ curator did. Using this method, she was able to date the manuscript within a 70 year range!

Got the date right +/- 70 years. That's pretty damn good and safer for the object than carbon dating. — Got the date right +/- 70 years. That’s pretty damn good and safer for the object than carbon dating.

It was nondestructive in that the energy level of the laser used didn’t “burn up” the ink sample. One of the issues that a conservator from the University of Michigan else mentioned during the Q&A portion was that in order to get the peak response that Ms. Goler got, she would destroy the sample. Since my experience with Raman spectroscopy is zero, I can’t really speculate why Ms. Goler was successful and this other woman from U of M was not.
I did think this is a really promising technique, provided I understood the content correctly. If people have edits or corrections, be sure to comment below!