A Puzzle without all the Pieces: Treating Papyri

Posted on December 7, 2020 by artifactlab

By Jessica Byler

The condition survey of our papyri collection is complete – I counted almost 4,300 fragments of papyrus and vellum, more than we realized were there! The papyrus ranged in size from a few millimeters to 9 feet long. Now, I have moved on to treating a few of the papyri that will be on display in the new Egyptian galleries.

Many of the papyri are sandwiched between pieces of Mylar. Static from Mylar can lift off friable ink or even split the two layers of the papyrus fibers and damage the papyrus. In order to safely remove the papyrus, I use a MinION 2 Ionizing Blower to eliminate the static charge. After removing the papyrus from the Mylar, I can then remove old repairs, realign fragments and fibers that are out of place, and apply new tissue paper bridges. Using a light box can help me identify joins and keep fragments in alignment. Papyrus fibers have different thicknesses, widths, and orientations, so transmitted light from a light box reveals the unique fiber pattern.

*Left: Removing papyrus (49-11-1) from a Mylar enclosure using an ionizing blower*
*Right: Using a light box to realign fragments*

Let’s look at one papyrus I am currently treating: a Temple robbery papyrus (49-11-1), dated to the 20th Dynasty or 11th century BCE. Along with removing old materials that might harm or obscure the papyrus, a key reason I am treating this particular document is to make sure the joins are right. It is fragmentary and there have been several treatment campaigns to repair it using a variety of materials, including Scotch tape, Japanese tissue, and Document Repair Tape.

*Temple robbery papyrus (49-11-1), before treatment*

I removed the old repairs where possible and reassessed the location of the fragments. At some point, several of the fragments have become misaligned or detached. In several instances, the fragments were just slightly out of line and could easily be nudged back into place. However, I quickly noticed some issues with a long fragment on the far left (on the right in the photo of the back below), and a small rectangular fragment at the bottom.

*Left: detail of the back of the right section before treatment*
*Right: Section under transmitted light from a light box, with red arrows pointing to the two fragments in the wrong spot*

On the long fragment, there are ink marks either side of the join which do not meet up. If the fragment was in the correct location, you would expect the writing to extend over the break. On the smaller fragment, the color, curvature, and thickness were different than the surrounding fragments. Using transmitted light, it is clear the fibers of these fragments do not actually line up correctly. Although at first glance they might not look out of place, they clearly do not belong there.

*Left: Detail of front, with red arrows pointing to ink which does not meet up*
*Right: Detail under transmitted light, with red arrows showing that the fibers do not line up*

The long fragment has two lines of writing at the top, so the number of locations it could join was limited. The small fragment at the bottom did not have any writing on it, so it was harder to determine its orientation and position. To add to this complicated puzzle, these pieces also might not join to any of the extant fragments.

*Left: Detail of back during treatment, with the two fragments, indicated with red arrows, properly aligned*
*Right: Detail of back during treatment, with red arrows pointing the two fragments, and blue arrows pointing to some of the new bridges; areas of white residue from the old materials is also visible*

Thankfully, their proper locations were easy to find using a light box. As you can see in the detail photos above, the fibers of the papyrus were a perfect match. The tissue paper bridges I used were around the size of a grain of rice and are clearly visible but blend in nicely with the papyrus. The Temple robbery papyrus is now ready for display!

*Temple robbery papyrus (49-11-1), after treatment*

This project is funded by the Antiquities Endowment Fund (AEF). The AEF is supported by an endowment established with funds from the United Stated Agency for International Development (USAID).

El cartonaje finalmente se relaja

Posted on December 12, 2019 by mollygleeson

por Teresa Jiménez-Millas

Durante el pasado mes, he tenido el privilegio de poder trabajar en un cartonaje egipcio, y ¡no menos es la suerte que tengo de poder escribir este artículo en mi lengua materna! Me han consentido mucho en este equipo.

Poco o nada sabemos de la procedencia de la obra, fue una donación a la colección egipcia del museo por parte del Sr. Thomas A. Scott en el siglo XIX, y es un estupendo ejemplar para estudiar tanto la técnica del cartonaje como el tipo de intervenciones que se hacían en el pasado.

La nomenclatura es una derivación del francés “cartonnage”, término usado en egiptología para hacer referencia a la técnica en la que finas capas de yeso se aplicaban sobre un soporte que podía ser fibra (lino) o papiro, permitiendo la flexibilidad suficiente para moldear y obtener las formas deseadas de la silueta del difunto, algo parecido al papel maché para que os hagáis una idea. Sobre este aparejo de yeso se elaboraban la policromía y el dorado.

Esta pieza ocupaba la zona pectoral de la momia. La imagen representa una figura alada con el disco solar sobre la cabeza, posiblemente Nut, quien junto a su hermano Geb eran los padres de Isis, cuya historia es central en la resurrección de los extintos.

En cuanto al proceso de restauración de esta obra, lo primero que nos llamó la atención fue el soporte adherido al reverso, que no formaba parte del original, y por otra parte el gran número de fracturas y pérdidas que presentaba el anverso.

Por la tipología de esta obra sabemos que no era plana y que tenía cierta curvatura, pues su función era decorar y descansar en el pecho de la momia. En este caso, parece que la persona que intervino la pieza en el pasado no tuvo en cuenta esto y añadió un cartón con mucho adhesivo en el reverso, de manera que la pieza ¡quedó completamente aplanada!

En este tratamiento de conservación lo fundamental era eliminar ese soporte trasero para relajar la obra, pese a que esto supusiera que los fragmentos antes unidos quedaran sueltos y desprendidos. Este paso se hizo mecánicamente con la ayuda de un bisturí y bajo las lentes del microscopio.

Se quiso evitar cualquier contacto con un medio acuoso, pues ante una obra tan frágil cualquier fluctuación de humedad podría afectar negativamente al soporte, a las capas pictóricas y al dorado.

Con el paso de los días se pudo observar cómo cada fragmento iba recuperando su forma primigenia, recobrando cierta curvatura y relajándose. Esto determinó el resto del proceso, pues se decidió no forzar la unión de las diferentes áreas. Cada una presentaba en este momento un diferente perfil y tratar de reunirlas provocaría mucha tensión innecesaria.

Se consolidaron y protegieron todas las zonas por el reverso y se estudió la mejor manera de realizar un soporte para cada una de ellas que permitiese también su futuro montaje y exposición.

Tras muchas pruebas, preguntas y mucha paciencia de mis colegas, se decidió que lo mejor sería hacer tres soportes para las tres áreas con resina epoxídica de madera; de esta manera cada uno soportaría un fragmento, un planteamiento respetuoso para la obra que nos hace entender que el paso del tiempo y las intervenciones del pasado dejan su huella.

Photos showing various trials for constructing a support for the fragile cartonnage pieces. The support in the third image (far right, made of wood epoxy) was the winner.

Tengo que agradecer a Jane Williams, jefa de conservación y restauración del “Fine Arts Museum of San Francisco” por sus consejos y su ayuda inestimable para el tratamiento de esta obra que tanto respeto me causaba.

Con mucha gratitud por haber tenido la suerte de trabajar con tan generosas personas y haber aprendido tanto en este fantástico proyecto, ¡espero algún día poder ver este cartonaje expuesto en el museo!

Este proyecto ha sido posible en parte por el Instituto de Servicios de Museos y Bibliotecas.

Treatment of a parchment scroll from Ethiopia: an objects conservator changes dimensions

Posted on July 17, 2019 by mollygleeson

by Teresa Jimenez-Millas

During the past month I have had the great opportunity of working on a parchment treatment under the supervision of Sarah Reidell, the Margy E. Meyerson Head of Conservation, Tessa Gadomski, Conservation Librarian, and the rest of the fantastic team in the Steven Miller Conservation Lab at the Penn Libraries’ Kislak Center for Special Collections, Rare Books and Manuscripts.

The parchment is an Ethiopian prayer scroll (29-94-123) in our Museum’s collection that we are treating for the opening of the Africa Galleries this November 2019.

In The Walters Art Museum online catalogue, there are similar scrolls to this one. The Walters describes them as, “Ethiopian prayer scrolls were made to be the length of the person who commissioned them, thereby protecting the owner from head to toe.”

This scroll is made of three sections of parchment sewn together using parchment strips/thongs (0.5 cm) from the same kind of animal. Parchment is a sheet material that is made from the skin of domesticated animals such as calves, sheep, and goats, cleaned of their hair and flesh and then dried under tension on a frame. It is a mechanical process and the skin is not chemically tanned. Further analytical methods such as scanning electron microscopy (SEM) or Peptide Mass Fingerprinting (PMF) would give us more information as to the kind of protein and other features that would help us to identify the type of skin.

The first step on this new and exciting project was a close examination of the object under a stereo binocular microscopic (Leica IC80HD). In my examinations, I noticed some interesting features that I would not have been able to understand without Sarah’s expertise, and I’d like to share some of these cool details here.

At first glance, the third section of the scroll has a 9 cm stitched repair that one might think was made after the parchment was manufactured. But as I learned, the process of manufacturing parchment involves drying the material under tension, which leads to marked changes in fiber orientation, and inevitably involves some degree of breakage of certain fibers in the dermal network.

Observation under magnification with Microscope LEICA IC80D we can see that the sewing holes are very round but are not punched. The holes appear to have been pierced when the skin was wet, and the parchment dried around the stitching creating ridged folds that are now keeping the split closed.

The thread is still present in about 25% of the repair. The edges of the thread are not cut but are frayed. At some areas we can still see some remains of black ink that also indicate that the scribe probably wrote over the repair. All these observations indicate that this repair was made during the manufacturing process of the parchment, while still wet.

I will write more about the treatment of this object in a future post!

Conserving Egyptian mummies…and more

Posted on November 16, 2016 by mollygleeson

Update – this post contains outdated language. We no longer use the term “mummy” and instead use “mummified human individuals” to refer to Ancient Egyptian people whose bodies were preserved for the afterlife. To read more about this decision, follow this link.

Recent visitors to the Artifact Lab may have noticed this new sign posted on one of the lab windows:

Since we opened in fall 2012, you might have occasionally caught us working on non-Egyptian things, but if you visit us now, you will definitely see us working on things from other parts of the collection, especially artifacts that we are preparing for our new Middle East Galleries. Right now, we are focusing a lot of our efforts on treating ceramics and lithics, most from Iraq and Iran.

We have tens of thousands of ceramics and lithics in this museum’s collection, but somehow, in my over 4 years here, I have gotten away with working on only a handful.

Conservator Tessa de Alarcon reconstructing a ceramic vessel. This is a common sight in our main lab (behind the scenes) but not so much in the Artifact Lab…until now.

So this is how, after spending over 4 years working on mummies and coffins, working on a small ceramic vessel becomes a novelty. And that is why I am going to walk you through some of the fairly routine steps of treating a ceramic, because I’ve never gotten a chance to write about it on this blog before, and honestly, I’m excited about it.

This small ceramic vessel with a simple striped pattern was excavated in 1931 in Ur, which is a site in modern day Iraq. It dates to the Ubaid Period, so is at least 6000 years old.

31-17-318, before treatment (BT)

As you can see in the above BT image, it was previously broken and repaired. In order to get it ready for exhibition, those old repairs need to be removed. We don’t always remove old repairs (and we never remove repairs that date to when the objects were still in use), but based on observations of the vessel and referencing an old conservation treatment report, I knew that the repairs had to be undone – if left in place those old materials are likely to fail and possibly cause more damage to the object. Another goal of the conservation treatment is to improve the appearance of the vessel, as there was excess adhesive and overpaint in areas and many of the joins were not well aligned.

Based on that old treatment report and tests in the lab, I knew that the old adhesive is soluble in acetone and that the material used to fill missing areas would soften in acetone enough to allow it to be removed. So the first treatment step, after documenting the piece fully, was to put it in an acetone vapor chamber:

An acetone vapor chamber isn’t anything fancy – in this case it was created with a plastic bag. I placed the vessel and 2 small containers of acetone in the bag and then clamped the open end to prevent the acetone from leaking out. Sometimes an object only needs a few hours in a vapor chamber before it can be taken apart. This little vessel required 24 hours before even one piece could be taken off. The whole thing was finally deconstructed after a week of sitting in the chamber on-and-off and poulticing and swabbing the joins with acetone.

During treatment, after the first piece detached

During treatment, after about half the vessel was taken down

During treatment, after more than half the vessel was taken down

Success! All the pieces are finally apart, placed on images of the vessel in order to keep track of everything.

Once the pieces came apart, I had to swab all the joins with acetone to remove excess adhesive and fill material. I’m now at the point where I will start joining the pieces together again.

Swabbing a break edge of a ceramic to remove excess old adhesive

Swabbing a break edge of a ceramic to remove old adhesive

Stay tuned for more posts about our work on these objects, and our continued work on the Egyptian collection and other projects!

Progress update on the stola coffin treatment

Posted on December 17, 2015 by mollygleeson

For the past few weeks, it has been full steam ahead on the treatment of the stola coffin lid. The lid is made of smaller pieces of wood joined together, then covered generously in areas with a thick layer of coarse mud plaster, followed by a thin layer of a finer mud plaster, followed by paint and a varnish. There are also raised details that were built up with gesso before painting.

This large piece of painted mud plaster (detached from the foot of the coffin, seeing on the left) is 11 cm thick.

This large piece of painted mud plaster (detached from the foot of the coffin, seen on the left) is 11 cm thick.

This area of damage clearly shows the wood substrate (green arrow), coarse mud plaster (blue arrow), and finer mud plaster (red arrow).

The two major condition problems on the coffin are found in the mud plaster layers: the coarse mud plaster has lost cohesion and in many places has separated from the wood below, and the finer mud plaster has also lost cohesion, so much so that it has deteriorated to a fine powder in places. I have spent over 150 hours so far readhering detached plaster, consolidating the powdery plaster, and realigning and stabilizing loose fragments on the coffin. Today I’m posting a few before and after treatment details to show the progress.

Here are before and after details of the top of the head showing an area where I had to readhere some large fragments of painted plaster:

Top of the head before (left), during (center), and after (right) reattaching painted plaster fragments

Here are before and after details of the left eye showing the consolidation of exposed powdery mud plaster:

Detail of losses near the left eye before, showing powdery mud plaster (left) and after cleaning and consolidation of the mud plaster in the losses (right)

And here is an area on the side of the head where I found that some fragments were previously attached in incorrect places. They were repaired long ago (with no documentation) with an adhesive that is soluble in warm water. I reversed the old repairs and found the correct locations for the fragments. I’ve outlined the fragments in their incorrect locations in the before treatment image on the right, below:

Detail of treatment on the side of the head before, with misplaced fragments outlined in pink (left), and after respositioning (right)

I still have lots of work to do before the treatment is complete, but I’m making good progress! I hope to be finished with the treatment early in the new year.

A closer look at our stola coffin lid

Posted on July 27, 2015 by mollygleeson

In my last post about this late 21st/early 22nd stola coffin lid, I referred to it as eye candy.

Overall before treatment image of the stola coffin lid, L-55-16B.

This coffin is beautiful, and we could discuss how nice it is to look at all day. But in this post, I’m going to focus on some of the more subtle, somewhat less-attractive (but perhaps even more interesting) features that I’ve discovered about this coffin lid as I’ve begun to work on it. In fact, on Friday I spent awhile discussing some of these details with a group of conservators and interns from the Philadelphia Museum of Art (PMA). As I mentioned in my last post, although this coffin has been on long-term loan to us since the 1930s, it still technically belongs to the PMA, so I am carrying out my treatment in close consultation with one of their objects conservators.

Penn Museum conservator Alexis North (far right) discusses a cat mummy with the PMA conservators and interns.

I always appreciate the opportunity for professional exchange, and I was happy to be able to discuss my plan, including materials and approaches with them. This discussion energized me to get started with the treatment, and that is exactly what I did, almost as soon as they left.

One thing that I noticed in my initial examination is that this coffin lid has been worked on before. There are residues of old adhesives in areas, including an adhesive mixed with a sawdust-like material, especially around the foot of the coffin.

Adhesive residues on an area of exposed wood near the foot.

I have seen these same types of repairs on at least one other coffin in our collection, and while there is no documentation of them, I am suspicious that this treatment was carried out in our museum soon after we acquired this coffin, but long before our conservation lab was established 49 years ago.

The foot of the coffin has another type of repair as well – there are 2 brackets that are held on with screws on the underside of the foot, apparently to secure some of the wood components. This whole area moves when handled, so the brackets and screws will have to come off so that I can better assess what is going on.

Detail of the foot of the coffin, showing the brackets used in an old repair.

There is some very powdery material associated with areas of damage, especially on the face, which appears to be partially due to deterioration of the mud plaster, but also may be due to insect activity. I’ll have to investigate this further over the course of the treatment.

Detail of the powdery material near the left eye.

And then there are some materials included in the mud plaster, including some course linen threads and even a leaf, which I am documenting as I work to clean the surface.

Detail of a detached piece of mud plaster with linen thread inclusions.

Detail of a detached piece of mud plaster with coarse linen thread inclusions.

Detail of an area of damage, which exposes a small corner of what appears to be a leaf caught in the mud plaster.

The next time I post images of this coffin lid, it should be a lot cleaner, as I plan to complete the initial surface cleaning within the next week. More soon about this, and other observations and developments in the treatment.

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