Looking inside our falcon mummy

Last Friday, 7 of us from our conservation department took a group of objects from the museum to the GE Inspection Technologies Customer Solutions Center in Lewistown, PA for x-radiography and CT scanning.

Our group gathered around the CT scanner, being operated by Becky Rudolph, GE's North American Radiography Sales Manager for Academia

Our group gathered around the CT scanner, being operated by Becky Rudolph, GE’s North American Radiography Sales Manager for Academia

Now, wait just a second, you might be thinking. Doesn’t Penn have its own x-ray and CT scanning equipment? Why did we have to take these objects all the way to Lewistown for this work? Good questions, and we have a good answer. We just received word that in early 2014, construction will begin on our new conservation labs, which will include a digital x-ray suite. We plan to purchase the x-ray unit from GE, so a visit to their facilities was a chance for us to demo the equipment using some of our own artifacts!

The object I was most eager to image was our falcon mummy. X-ray and CT (computed tomography) scanning technology allow us to “virtually unwrap” this mummy, helping us understand how it was made and what is inside (and as visitors to the lab have heard me say, we can’t assume that there are any falcon remains inside-we can only hope!).

The falcon mummy laying on its storage support on the x-ray plate (within a lead-lined room)

The falcon mummy lying on its storage support on the x-ray plate (within a lead-lined room)

The quickest way to get a peek inside the falcon mummy’s wrappings is by taking an x-ray image. Digital x-ray technology is amazing – with a push of a button, 135 kV (kilovolts, measurement of the voltage), 2.0 mA (millamperes, measurement of the current) and 4 seconds later, we saw this:

falcon xray annotatedHooray! In this first attempt, we could already see that there are bird remains inside. The bright white material concentrated in the center of the mummy wrappings is the skeletal remains. In radiographic images, materials that are denser appear white because they do not allow x-rays to pass through. Materials that are less dense (such as the textile wrappings surrounding the bird bones) appear darker, because the x-rays are penetrating and passing through these materials. We can see in the image above that there are no skeletal remains in the “head” and the “feet” of the falcon mummy – these areas appear to have been sculpted with fabric. The slightly brighter white area near the feet just reflects an overlap of textile in that area.

While we were excited by this image, it immediately prompted more questions. We can see bird bones, but where is the skull? How much of the bird body is present? Are there any clues as to how the body was prepared for mummification? To answer these questions, we turned to the CT scanner.

CT scanning uses x-rays to produce cross-sectional images of an object, which can then be combined to produce three-dimensional views. CT provides a much more detailed look inside objects, and better distinction between different materials.

The CT unit at GE does not look like a medical CT scanner that many people may be familiar with. To scan the falcon, we had to stand the mummy upright in its box, which we then secured to the rotating stage inside the CT chamber with masking tape.

Right: Lynn Grant and I taped the falcon mummy in his box to the stage inside the CT chamber. Left: another view of the falcon mummy's box secured inside the CT chamber.

Left: Lynn Grant and I taped the falcon mummy in its box to the stage inside the CT chamber Right: another view of the falcon mummy’s box secured inside the CT chamber

The CT scanning took a bit longer than 4 seconds, but again, produced much more detailed images. Here is what one of the cross-sections looks like:

falcon cross section annotatedIn this image, the bones are visible as the most radio-opaque materials (so they are bright white). We were also excited to see the feathers, clearly visible as little circles reflecting the cross-section of the feather shafts, which are hollow. The various layers of linen wrapping are also very clear – clear enough to count! But other details are not so immediately clear to us, including the presence of the skull, and exactly how the remains were prepared.

Here is a screen shot from the program we are using to view the CT images, showing 3 different cross-sections, and a basic 3D rendering of a section of the falcon mummy. In this 3D rendering, we can clearly see the falcon’s talons, circled in red!

falcon CT 3 views annotatedWe will need to spend time with the images, and consult other specialists, to better understand what the CT scans have revealed.

image_2

UCLA/Getty graduate intern Alexis North and I puzzle over the CT images of the falcon mummy

We will follow up later with more images and interpretations of the falcon mummy CT scans, plus more about the other objects we were able to examine.

A special thank you to Becky Rudolph and Hank Rowe at GE for spending the day with us, and for their expertise!

 

X-ray excursion

If you stopped by the Artifact Lab this week, you might have noticed that our falcon mummy is no longer on display, and this sign in its place:

falcon signAs indicated on the sign, the falcon has been removed for x-radiography. This mummy has never been x-rayed before, and we’re interested in using this imaging technology to learn how it was made and if there are any falcon remains inside!

Along with the falcon, we’re also going to be x-raying/CT-scanning our (possibly headless) cat mummy, the wooden statue heads, and several other pieces.

We do not have the ability to x-ray and CT-scan objects here in the museum, so we will be taking these selected pieces for a little trip tomorrow. In preparation for their travels, they are securely packed, and ready for this exciting excursion!

The falcon mummy is secured inside its storage support and packed into a larger box for travel.

The falcon mummy is secured inside its storage support and packed into a larger box for travel.

We will update the blog with our findings soon after we return.

 

Examinations of a baby boy mummy

I think it’s about time we introduce you to a special occupant of the Artifact Lab.

This baby boy mummy, who dates to the Third Intermediate Period (1075-656 BCE), has been in our collection since 1898, when he was donated to the museum by Dr. Henry Shurtleff.

Photograph of the baby boy mummy from the museum Archives

Photograph of the baby boy mummy ca. 1930

In the University’s 1898-1899 Annual Report of the Provost to the Board of Trustees, it states that Dr. Shurtleff presented the infant mummy to the museum on Christmas Day, as an “admirably preserved specimen and an interesting pathological subject”.

It seems that this mummy came into the collection unwrapped – he only has small amounts of textile preserved on his body (and there is currently no evidence that the cloth partially covering his body in the image above is related to his remains, but this remains to be determined). While the fact that he is unwrapped is unfortunate, it allows us to see how well preserved his remains are and evidence of how his body was mummified, including evisceration through an incision on the left side of his torso.

The open incision on the left side of his body reveals a mostly empty body cavity, containing small bundles of linen.

The open incision on the left side of his body reveals a mostly empty body cavity, containing small bundles of linen.

A CT scan in 2009 further reveals how this boy’s body was mummified, and also reveals damage not visible from the exterior. For example, it is clear that his brain was removed, likely through the nose (but due to the small side of his nasal bones it is not possible to see evidence of this). The scan also reveals a large hole in the left lower side of his skull, and the piece of missing bone resting inside his skull.

Two CT still images show the child mummy's skull with a piece of bone resting inside the cranium (left) and the hole on the lower left side (right).

Two CT still images show the child mummy’s skull with a piece of bone resting inside the cranium (left) and the hole created as a result of this loss (right).

Oddly, this damage to his skull is not visible from the exterior, but it may be the result of trauma. His cause of death has still not been determined, but this damage may provide a clue.

The information from the CT scan tells us that this child was less than 2 years of age when he died, based on the fact that his fontanelle (the soft spot) is still open, and also on the development of his teeth.

The open fontanelle on the top of the baby's head is indicated in these 2 images with blue arrows.

The open fontanelle on the top of the baby’s head is indicated in these 2 images with blue arrows.

The excellent preservation of his body is not the only remarkable thing about this baby boy. While examining his remains, we noticed traces of a green substance in areas, including on his face and fingers.

A detail of the green substance under the boy's right eye (left) and an overall view of the boy's face, highlighting the locations of the green substance in green (right)

Left: A detail of the green substance under the boy’s right eye. Right: An overall view of the boy’s face, highlighting the locations of the green substance in a brighter green color.

This substance resembles copper corrosion, and it may either be corrosion from copper that was once in contact with his body (during burial), or may be traces of a green copper-based pigment. How do we know this green substance is copper-based? We tested it with our portable x-ray fluorescence analyzer, which showed high peaks for copper in these areas.

While we’re still working to interpret some of this information, I can tell you one thing for certain: this baby boy mummy sure is special. And if you visit the lab, you just might catch a glimpse of him.

 

The 2013 Mummy Congress in Rio de Janeiro

Today we are featuring another guest-blogger: our pre-program conservation intern Melissa Miller. Melissa just returned from a pretty special mummy-related trip – read on to hear more about it!

From August 6-9th, I had the opportunity to travel to Rio de Janeiro, Brazil and attend the 8th World Congress on Mummy Studies.

IMG_2766This biannual conference brings together experts from all over the world to discuss recent and ongoing mummy research projects.

Mummy studies draw in a surprising variety of disciplines. There were experts in physical and cultural anthropology, conservation, paleopathology, paleoparasitology, dentistry, medicine, radiology and more. I listened to presentations on ancient DNA techniques, publishing e-books, parasites in coprolites, archaeological excavations in the Valley of the Kings, genetic analysis of the Iceman, and the list could go on. For 4 days I received a crash course on numerous mummy research projects from all over the world that have been going on for the last 15 years. Thankfully the Congress was videotaped and I will be able to revisit some talks or view some that I was unable to attend due to conflicts with other presentations.

melissa mummy congressWhile there, I was also able to present a poster on my ongoing research into the history and development of autopsied mummies, and the preservation of generated materials. For me this was perhaps the most valuable part of my experience at the Mummy Congress. Simply meeting all of these incredible and passionate people and listening to their advice, hearing their encouragement and seeing their willingness to help me continue my research was invaluable. Some have also granted me permission to interview them!

Looking towards the future, I plan to continue my research throughout the academic year and develop my senior thesis. Perhaps by the time the 9th World Congress rolls around I will be able to present my finished project!  Lastly, I would like to say that I am very grateful to all those at the University of Delaware and University of Pennsylvania Museum of Archaeology and Anthropology who made it possible for me to attend the Mummy Congress, and to all those at the Mummy Congress who offered their great advice and support.

 

Field trip!

Sometimes getting started on a conservation treatment requires getting out of the lab for a bit, so this week, my colleague Julie Lawson and I took a field trip down to Baltimore to visit the Johns Hopkins Archaeological Museum and chat mummy treatments with their Curator/Conservator, Sanchita Balachandran. Sanchita and I connected at the American Institute for Conservation (AIC) annual meeting back in June – I had read about a treatment that she carried out on a human mummy at the museum, and when we realized that we both had animal mummies in our labs as well, we decided we’d get together for a brainstorming session to discuss treatment approaches, materials, and storage options for these fragile objects.

Julie Lawson admires artifacts in one of the cases in the Johns Hopkins Archaeological Museum

Julie Lawson admires artifacts in one of the cases in the Johns Hopkins Archaeological Museum

The Johns Hopkins Archaeological Museum is nestled in the center of the Johns Hopkins Homewood Campus in Baltimore, in a beautifully-renovated building, surrounded by classrooms and light-filled student study spaces. The museum was established in 1882 and since its founding, has been dedicated to inspiring and teaching students at the university.

One of the main features of the museum is the display of archaeological objects from ancient Greece, Rome, Egypt, the Near East, and the ancient Americas, displayed in glass case walls, allowing students, faculty, and visitors to view these pieces and peer into the museum itself.

museum2_compThe museum also displays pieces on loan, including an ancient Egyptian mummy from Goucher College.

Goucher mummyThis was the mummy that I had read about and was curious to learn more about from Sanchita. The Goucher mummy is an adult female mummy from the Ptolemaic Period (305-30 BCE), and I knew some details of the treatment from Sanchita’s article in the Journal of the American Institute for Conservation (JAIC), but this was a great opportunity for me to see this mummy up-close and to ask Sanchita more about how she approached this treatment and the specific materials and techniques she used. Since we are in the middle of working on the treatment of our mummy PUM I here in the Artifact Lab, this conversation was very timely.

Detail of the Stabiltex encapsulating the feet of the Goucher mummy

Detail of the Stabiltex encapsulating the feet of the Goucher mummy

The Goucher mummy has a fascinating history that I won’t get into here, but you can learn more about her in the “Object Stories” section of the museum’s website by following this link. One of the things I was curious to discuss more with Sanchita was her use of Stabiltex, a sheer polyester fabric, to protect fragile areas of the mummy’s wrappings, and the design and construction of the support the mummy is currently resting on in the exhibit. As I said, we’re working on encapsulating PUM I’s outer linen wrappings in a similar way, but using a different type of sheer netting fabric. After discussing techniques with Sanchita and seeing how successful her treatment of the Goucher mummy was, I returned to the Artifact Lab feeling good about our approach to PUM I’s treatment!

Sanchita also pulled out several animal mummies that she is currently working on, including these cuties:

Cat (above) and dog (below) mummies

Cat (above) and dog (below) mummies

We discussed the challenges of dealing with such fragile linen wrappings and our experiences with and use of different adhesives, as well as techniques for encapsulating fragile areas. Sanchita also showed us their handling and storage mounts, which go a long way in protecting these artifacts.

Sanchita lifts an ibis mummy from its storage box using a handling tray

Sanchita lifts an ibis mummy from its storage box using a handling tray

After discussing mummies at length, Sanchita took us back into their storage area, where we had the opportunity to see additional Egyptian artifacts, including several painted wood artifacts with a variety of condition problems. As readers to this blog may know, we have our own fair share of challenging painted wooden artifacts, including Tawahibre’s coffin, so I was eager to see how Sanchita was approaching the treatment of these pieces as well.

Sanchita and Julie in storage

Sanchita and Julie in storage

All in all, it was a fun and productive day! These types of professional exchanges are incredibly valuable, and I’m not only inspired to tackle some treatments and try new things back in the lab, but to make more time in the future to visit other colleagues and collections. A huge thanks to Sanchita for hosting us and for sharing so much about her work at Johns Hopkins.

 

Conservators-in-training

For over 10 years, our museum has organized an “Anthropologists in the Making” Summer Camp, and today we hosted 66 of these summer campers in the Artifact Lab for an afternoon of conservation training.

IALSummerCamp1This year the camp is being held over 8 weeks, with different themes each week, including Can you Dig it?, all about archaeology, and Visions and Dreams, which explores the significance of dreams and the roles of shamans and mystics (this one is coming up in August).

The camp theme this week is Mummies Unwrapped so of course we had to give the campers a taste (but not literally) of mummy conservation, in addition to what they are learning about mummies and ancient Egypt.

We organized 3 different activities for the 7-13 year olds (they were split into 2 groups according to age) to test their hand and observation skills. All 3 activities were created to mimic some of the work that we’ve been doing in the Artifact Lab, including:

- an excavation station, which challenged the campers to pick out the remains of a beaded shroud from a bin of mummy debris (similar to recovering PUM I’s beads)

IALsummercampexcavation2

- a cleaning station, where campers tried different cleaning tests to remove dirt from a painted ceramic tile (like the cleaning that we’ve been doing on our painted coffin of Tawahibre)

IALsummercampcleaning4

- a materials ID station, where the campers had the opportunity to examine “mystery” materials under magnification and then had to identify what they were looking at (an example of one of the material ID challenges we’ve encountered in the lab can be found here)

A camper compares reference materials to the magnified image of the "mystery" material on the monitor

A camper compares reference materials to the magnified image of the “mystery” material on the monitor

For each activity, we had the kids fill out worksheets to record their observations, to give them a sense of the documentation involved in our work. Before moving on to the next station, each camper needed to get their supervising conservator to sign off on their worksheet. On their way out the door, all campers received certificates declaring them “Junior Conservators for-the-day”.

certificateWe had lots of fun, not only preparing for the camp

Arts and crafts day in the Artifact Lab (left) and the painted tiles before "dirtying" them for the campers (right)

Arts and crafts day in the Artifact Lab (left) and the painted tiles before “dirtying” them for the campers (right)

but also working with the kids at each of the stations. We were impressed with their observations and how quickly they picked up on each activity (rolling swabs can be hard at first!). Special thanks to our Education Department and to all of the summer campers for increasing our department more than tenfold for the afternoon!

IALsummercampcleaning1

 

Preparing to “re-wrap” PUM I

It’s been a busy week in the Artifact Lab, and I was fortunate to have lots of help from our University of Delaware pre-program intern Melissa Miller and our summer graduate intern from Cardiff University’s conservation program, Anna O’Neill.

Anna O'Neill repairs the linen on one side of PUM I's body

Anna O’Neill repairs the linen on one side of PUM I’s body

As I’ve written about previously, I have been working on the stabilization of some of PUM I’s linen on his head, chest, and body. You can read a little more about it by following this link.

This week, Melissa, Anna and I continued to relocate and repair detached linen fragments from the outer shroud and the narrow bands wrapped around PUM I (thanks to Tom Stanley in our Public Relations office, there’s a great photo of us doing this work on the museum’s facebook page). Just to give you an idea of what is involved, here are some photos documenting the process:

From top left: detached linen before reattaching with strips of Japanese tissue paper (indicated by red arrows), after reattachment, and after rejoining with the rest of the surrounding linen

From top left: detached linen before reattaching with strips of Japanese tissue paper (indicated by red arrows), after reattachment, and after rejoining with the rest of the surrounding linen

All of this work is in preparation for the encapsulation of PUM I’s outer shroud using nylon bobbinett, or netting. Encapsulating the mummy with a sheer material like the nylon netting will help to hold many of these fragile areas together and will provide support and protection for this very deteriorated fabric, BUT because it is so sheer, it will still allow details of the linen to be seen. I used a similar technique to protect the linen on the “feet” of our falcon mummy (see our post about this here).

The nylon netting is white, so we need to tone it to a color similar to the linen before use. Yesterday, Anna worked diligently to find an appropriate color – here is a shot of her color matching and testing in progress:

PUMI toning nettingRe-creating the color of “mummy cloth” is harder than you’d think – the linen is not all the same color, so we need to find a color that will blend in well with the various shades.

In the upcoming weeks we hope to start “re-wrapping” PUM I and then begin the process to reassemble all of his various pieces. As usual, there’s always something exciting to see in the Artifact Lab!

 

Investigation of a mummy bead “coating”

While we continue to work on the conservation of PUM I‘s remains, we also have been taking this opportunity to carry out some analysis on the residues and substances preserved on his wrappings and on the beads that once made up his beaded burial shroud.

Since the last time we wrote about these beads, we have recovered even more in the conservation process; we now have a total of 35 beads – all either tubular or circular in shape. As we wrote about in a previous post, all of the beads are covered with concretions, mostly a brown, waxy material. Here is an image of one of the beads before cleaning, and after partial exploratory cleaning, revealing the beautiful blue color of the bead:

A tubular bead before (left) and after (right) exploratory cleaning to remove the residue on the surface ( 10X magnification)

A tubular bead before (left) and after (right) exploratory cleaning to remove the residue on the surface ( 10X magnification)

This material does not appear to be dirt or accumulated debris from the mummy. But, it can be removed rather easily from the beads, especially with the help of some mineral spirits, which suggested to me that it is some sort of wax.

Based on this information, I was suspecting that either this material was related to a substance applied to the beads to help the beaded shroud stay in place at the time of burial (but we have yet to locating any research supporting this theory – it was more common to sew or tie these beaded shrouds in place) or that it is related to a substance applied to the shroud at the time of discovery, to assist with the removal of the shroud.

In conservation, when it comes to investigating unknown, likely organic substances, there are several analytical techniques that can be helpful. One of these techniques is Fourier-transform infrared (FTIR) spectroscopy. FTIR works by exposing a sample to infrared radiation, which causes the sample to selectively absorb radiation, depending on the molecules present. The individual peaks in the resulting absorption spectrum can be analyzed or the spectrum can be compared to reference spectra to help characterize or identify a material.

We provided a small sample of our “bead coating” to Gretchen Hall, a consulting scholar in the Biomolecular Archaeology lab here at the museum. She ran the sample for us and provided the resulting spectrum and interpretation. Here is the spectrum produced by our sample:

E2813A_FTIR_beadThis spectrum shows that the sample is mostly organic as evidenced by the dominant peaks in the 2900 cm-1 region which are characteristic of C-H bond stretches.  In addition, there were many peaks in the “fingerprint” 1800-1000 cm-1 region where various organic molecules absorb. The absorption around 1730 cm-1 (due to C-O double bond stretches) suggests organic acids are present, possibly from resins or beeswax. Both of these families of compounds would also have bands around 1470 (a O-H bending absorption) which are seen in our sample. Importantly, the sample also shows a strong band around 720-730 cm-1 (due to the C-H in long hydrocarbon chains) which is only present in beeswax.

For comparison, here is our bead coating sample spectrum displayed just below the spectrum for a standard beeswax:

E2813A_FTIRBased on this analysis, our “bead coating” sample likely contains some beeswax, which is consistent with our observations of the solubility and consistency of the material as well. It is known that beeswax was used in ancient Egypt – as an adhesive, a sealant, a binding medium, and in the mummification process. Bees were considered by the Egyptians to be precious insects with magical and economic prestige, and these values would have extended to their wax (Ikram and Dodson 1998).

For a more definite identification of our sample, the next step would be to analyze the material using gas chromatography–mass spectrometry (GC-MS).

Special thanks to the Biomolecular Archaeology Lab and Dr. Gretchen Hall for running this sample and providing the analysis.

 

Unwrapping mummies?

If there is one thing that I try to emphasize to visitors to the Artifact Lab, it is that we are NOT unwrapping or cutting open mummies. While this type of examination may have been appropriate and acceptable in the past (think PUM I) we don’t do this anymore. As you may gather from the title of this blog and our project, we are focusing on the conservation of our mummies, and we do this by aiming to use non-invasive and reversible examination and treatment techniques as much as possible. Our ability to carry out our work with much less interventive procedures than those used in the past is due in part to advances in technology. And when you see what is possible with new technology, you can see why autopsying mummies just doesn’t, errr…cut it.

Take, for example, one of our mummies that was CT-scanned back in 2009.

Hapi-Men on display in the Secrets and Science exhibit

Hapi-Men on display in the Secrets and Science exhibit (Hapi-Puppy is by his feet!)

As part of a larger CT-scanning project funded by the National Science Foundation, Hapi-Men, along with his puppy (Hapi-Puppy) was CT-scanned at the Department of Radiology at the Hospital of the University of Pennsylvania (HUP) (a special thanks to Felicia Williams and Erica Durham for this work!).

Although Hapi-Men had been x-rayed in the past, this type of examination is limited in that it does not provide much detail of any of the preserved soft tissue and other materials (like amulets) included in the mummy’s wrappings. But CT-scans can help reveal these details, and they also allow for 3D reconstructions, like the one you can see below, created by Penn graduate Samantha Cox under the supervision of Dr. Janet Monge.

CT-scanning, combined with other imaging techniques such as photogrammetry and laser scanning, leads to some pretty amazing virtual representations of mummies. Most recently, such work has been carried out in a collaborative effort between The Museum of Mediterranean and Near Eastern Antiquities in Stockholm, a group of Swedish visualization researchers, FARO (a 3D technology company) and Autodesk (a software company focusing on 3D design). This collaboration has resulted not only in the capture of new information for researchers, but the creation of an interactive exhibition for museum visitors, scheduled to open in Stockholm in February 2014. The interactive part of the exhibit, created using Inside Explorer will allow both museum staff and visitors to use simple gestures to virtually unwrap the mummies and to explore their multiple burial components.

You can read more about this exciting project, and see several images and videos of the process by following this link.

Our current work to conserve the mummies and funerary items In the Artifact Lab will stabilize some of these fragile objects enough to allow us to CT-scan them, and hopefully so that we can create some of our very own interactive exhibition features in the future.

 

New objects in the Artifact Lab

Starting today, there are three new artifacts on view in the exhibit space here in the Artifact Lab. Those of you who have been keeping up with this blog will recognize these pieces, including:

Our falcon mummy:

falcon in caseTanwa, one of our child mummies:

Tanwa in case

and Nefrina’s cartonnage mummy mask:

nefrina in caseAll of these artifacts are displayed with labels explaining their conservation “story”.

In addition, we have a binder available in the exhibit space that includes the conservation treatment reports and images for each of these artifacts. These reports contain detailed descriptions of the materials and the condition of these artifacts, and of the techniques and materials used to conserve them.

Of course, we also have information about these pieces here on our blog, and later this week we will post more information about the process of conserving Nefrina’s mummy mask.