Out with the old, in with the new

There are some new objects to see in the lab!

Just this week, we began returning some of our recently-treated objects to storage and exchanging them for some new stuff, including a painted wooden coffin (this is a photo of the coffin box without the lid – note the elaborate painted decoration on the interior):

coffina falcon coffin and “mummy” (I’m putting “mummy” in quotes here because this mummy looks like it’s a corn mummy, made by wrapping up a mixture of sand, grains, and plant fibers):

falconmummythese pieces of a painted wooden coffin board with two Wedjat eyes:

coffinboardand this ibis mummy, with exposed feathers!

ibismummyThere are some other things too, including some cartonnage and another animal mummy, which we’ll post photos of soon.

As always, these photos really don’t do these objects justice. You’ll have to come check them out in person! And we’re only just starting to examine them, so we’ll definitely post information as we learn more. If you have specific questions about any of these objects, please let us know!

 

Wood ID

I’m currently treating 7 fragments of a painted wooden coffin from Abydos. Lately, many of our visitors have been asking what kind of wood was used to make this coffin. This has actually been a question that we have been asking ourselves, and we are trying to see if we can come up with an answer.

In ancient Egypt, large timbers for coffin-making were scarce, so the wood was either imported from places like the Mediterranean, the Near East, or from other parts of Africa, or the Egyptians would cobble together smaller pieces of wood from local sources. Based on previous studies, we have a finite list of types of wood that are known to have been used, but from there we need to move to looking at the object itself.

These images show the exposed wood on the side (left) and back (right) of one of the coffin fragments. Can you guess what type of wood this might be?

These images show the exposed wood on the side (left) and back (right) of one of the coffin boards. Can you guess what type of wood this might be?

As conservators, we are educated not only in object treatment, but in the analysis of objects, and the examination of tiny fragments of objects, like plant and textile fibers, wood, and pigments. But many of us don’t do wood ID all that often, so it can take awhile to get set up, to re-orient ourselves to what we’re seeing in the samples, etc. AND it requires a sample, which we don’t often have access to. Fortunately, for me, I have some already detached samples from these boards and access to someone who does this type of work more frequently, archaeobotanist Dr. Naomi Miller, so I turned to her to help me with this work.

Dr. Miller looked at the samples I had and selected one that looked promising, due to the exposed cross-section on one end. I mounted this sample under our binocular microscope and took a photo, to help her study it further and compare to known reference samples.

E12505_woodID

The wood fragment with exposed cross section, 60X magnification

From this sample, Dr. Miller was able to determine that this is a hardwood, based on the presence of clearly visible rays and thick-walled pores, many of which are radially paired (pointed out below).

Slide4Based on these features and the known types of hardwoods used in ancient Egypt, this helped narrow down the likely possibilities to Common ash (Fraxinus excelsior L.), Carob (Ceratonia siliqua L.) and Acacia (Acacia sp.). Dr. Miller considered other types but ultimately excluded willow (Salix), oak (Quercus), elm (Ulmus) and sycamore fig (Ficus sycomorus) due to either the presence or absence of certain features.

In an attempt to further narrow down the possibilities, I cut thin sections from the sample that Dr. Miller examined, from the cross-section and tangential surfaces, and wet-mounted them on glass slides. Looking at these thin sections with our polarizing light microscope (PLM), I was able to see some of these features a bit more clearly.

Cross-section, 50X magnification

Cross-section, 50X magnification

In the cross-section above, the pores are visible as solitary or paired, and mostly uniseriate (1-cell wide) rays are visible. The tangential section also shows mostly uniseriate rays, but some bi-seriate rays are visible as well.

Tangential section, 50X magnification

Tangential section, 50X magnification

Cutting these sections from the wood sample, which was quite degraded, was difficult and unfortunately I’m not really able to pick out many other features from the sections that I examined. I will have to get Dr. Miller to weigh in on this again, but in the meantime, I’m going to go out on a limb and say that I’m leaning toward this wood being acacia. One thing I forgot to mention is that the wood of the coffin board fragments is a deep red-brown color. Acacia is known for being a red, hard, and durable wood, and while it produces small timbers, we know that it was used for coffin-making, among other things.

Treating fragments of a Middle Kingdom painted wooden coffin

If you’ve visited the lab in the last few weeks you may have seen me, head bent at the binocular microscope, working away on fragments of a painted wooden coffin from Abydos. These fragments (7 in total) were excavated in 1901 and have been here at the museum ever since. As I described in a previous post, these boards were severely damaged by termites prior to excavation, and the painted surface, while very well-preserved in some areas, was cracked, flaking, and barely attached in places, not to mention covered with grime.

One of the coffin fragments, which features a portion of a frieze of objects that includes two vessels with spouts and a bolt of clothing.

A before treatment photograph of one of the coffin fragments, which features a portion of a frieze of objects that includes two vessels with spouts and a bolt of clothing.

On the board in the image above, the paint was actually in decent condition. After cleaning the surface with bits of a kneaded rubber eraser, I stabilized the edges around the paint losses with a 2% solution of methyl cellulose in water. With the help of an intern, we sorted through a box of much smaller fragments that presumably had become detached from the 7 larger boards at some point, and we found two small fragments of wood with painted decoration which belonged to this board. These fragments were adhered in place with a 1:1 mixture of 5% methyl cellulose and Jade 403, an ethylene vinyl acetate emulsion.

E12505emends

In this image the red arrows point out the two fragments which were adhered in place after cleaning and consolidation.

Here is a view of that area from the back after mending those fragments:

e12505e_backbeforemendingThe termite damage is evident from the back, and as you can see, the wood is very thin in this area in particular, only about 1mm thick along the join edges between the small fragments and the larger board. The small loss to the right of the upper fragment is an area where the wood and painted surface have been lost completely.

Because the wood is so thin and fragile, I decided to provide some support to this area, by first adhering a piece of Japanese tissue paper over the loss from the back with a 5% solution of methyl cellulose.

e12505e_backmend

A detail of the Japanese tissue paper support adhered over the loss

I then filled the loss and the small gaps along the join edges of that upper fragment from the front, using a fill mixture made from 5% methyl cellulose, glass microballoons, and powdered pigment.

e12505edetail

A detail shot showing the fill from the front

Here is an overall view of the board, after treatment:

E12505Edt02_blogThe fill mixture I used worked nicely, and I’m now using it to stabilize the edges of some of the lifting paint on the other coffin board fragments where the painted surface is in worse condition. I will post photos soon showing what the coffin boards look like before and after treatment.

 

Completing the treatment of Tawahibre’s coffin

Things have been pretty busy around here lately, and I almost forgot to post some updates about several projects. One project in particular is the treatment of Tawahibre’s coffin. We have been working on this 2-part painted wooden coffin in the lab for the last year, and we recently completed its treatment.

As you may remember, when the coffin first came up here, it was covered with a thick layer of dust and grime, the paint was badly flaking in areas, several large pieces of painted gesso were pulling away from the wood support, and there were large cracks throughout.

Before treatment photos (clockwise from left): upper half of coffin showing layer of dust and large cracks and losses; large piece of painted gesso partially detached from top of head; large loss on wig, showing old animal glue adhesive from a previous restoration

Before treatment photos (clockwise from left): upper half of coffin showing layer of dust and large cracks and losses; large piece of painted gesso partially detached from top of head; large loss on wig, showing old, shiny animal glue adhesive from a previous restoration

After cleaning the surface with a brush and vacuum, followed by cosmetic sponges, I consolidated the paint with a methyl cellulose solution, filled in cracks and gaps using Japanese tissue paper and a mixture of methyl cellulose bulked with cellulose powder and glass microballoons, and then toned the fills with acrylic paint. This work is explained in further detail in previous posts, which you can find by clicking on the links included in blue above.

fillingcracks

A detail shot of the wig showing an area with several large open cracks before and after filling with Japanese tissue paper and methyl cellulose/cellulose powder/glass microballoons mixture

Based on a discussion with our Egyptian section curators, I also made some aesthetic fills to mask some large losses, including 2 losses on the wig. We chose not to fill the losses on the nose and chin because filling these losses would require too much guess-work as to the original contours of these features.

Large loss on wig before (left), after application of Japanese tissue paper layer (middle), and after application of fill mixture (right)

Large loss on wig before (left), after application of Japanese tissue paper layer (middle), and during application of fill mixture (right)

Detail of the head and wig before (left) and after (right) conservation treatment, with losses in before treatment photo outlined in red

Detail of the head and wig before (left) and after (right) conservation treatment, with losses on the wig outlined in red. The larger loss on the right is the featured in the previous series of images.

I carried out similar work on the base of the coffin, and now both are complete:

Tawahibre's coffin lid before (left) and after (right) conservation treatment

Tawahibre’s coffin lid before (left) and after (right) conservation treatment

The coffin base before (left) and after (right) conservation treatment.

The coffin base before (left) and after (right) conservation treatment

As you can see, we chose not to fill many of the losses, focusing instead on stabilization.

This work will enable future exhibition of the coffin, and just as importantly, it will make further study of the coffin possible. All along there have been some discrepancies between the name that has always been associated with the coffin (Tawahibre, a woman’s name) and a previous translation in 1946 of the hieroglyphic text on the coffin (which identified the name of a male court official, the son of J-se(t)-N-Ese). There has also been some confusion about the remains once housed in the coffin, which were previously identified as male, but in a 1975 autopsy the remains were confirmed as belonging to a female in her mid-30s. A bit confusing, but hopefully we’re now one step closer to getting this all straightened out!

 

What is under the paraffin ?

Egyptian wooden statue of Ka-Aper, also named  the Sheikh-el-beled, from the Vth Dynasty, decorated with inlaid eyes.

Egyptian wooden statue of Ka-Aper, also named
the Sheikh-el-beled, from the Vth Dynasty,
decorated with inlaid eyes.

Quite a while ago, we dealt with the treatment chosen for the two Egyptian wooden heads and now it’s time to talk about its results. Let’s focus on the cleaning of the surface: the goal was to remove the paraffin that certainly masked other remains of the painted layer.

First of all, we have to talk about the notion of original surface and original level.

> The original surface is composed of the original materials, before they were buried and underwent an alteration process. Concerning the heads, it corresponds to the paint layer they were decorated with.

> The original level is a layer of altered material that took the place of the original material but remained at the same level as the original surface. A good way to understand this is to think about a fossil: it is no longer the original animal, insect or plant made of flesh, bones, shell that it used to be…but you can still identify its shape since it was precisely petrified by another material. That’s what we can call the original level of an object surface.

Nouvelle image (2)It was necessary to define what the original level was on the heads, so as to know how deep the cleaning could go. It had to keep its meaning regarding the object itself. The paint layer was a good clue since these colored patches were all that remained from the original surface. As far as we could see, the rest of the surface was more or less corresponding to the original level. Indeed, there was no important gap between the painted areas and the present surface.

Sans titre - 1

Original surface and original level near the wig of E17911, x7.5 magnification.

Another issue with paraffin was to think about how much of it we wanted to remove. Indeed, this sticky layer seemed to be what was holding the elements of the current surface together. That was especially true about the painted areas. Concerning the wood, we could only suppose that the paraffin had penetrated inside on a few millimeters only (thanks to a few articles that were published and gave estimations of paraffin migration inside archaeological wood) since we had no way to obtain an accurate estimation of this. Therefore, we didn’t want to remove it completely from the wood because it could threaten its stability and cause the wood to crumble.

That’s why the cleaning began with the known rather than with the unknown: the painted areas were cleaned from the paraffin that covered them. Thus, we could see their real extent. However, the pigments remain stuck in a thin paraffin layer but their legibility was improved, as you can see on these pictures:

Pictures of E17911’s right cheek before and after cleaning, x7.5.

Pictures of E17911’s right cheek before and after cleaning, x7.5 magnification

Nouvelle image (15)

Pictures of E17910’s chin before and after cleaning, x7.5 magnification.

E17910’s right eye, before and after cleaning.

E17910’s right eye, before and after cleaning.

Then began the exploration of the unknown side of the heads, meaning the rest of the surface, where the presence of areas of paint was only a supposition.

This part of the work was really the longest since we couldn’t know what to expect under the paraffin and sediment layer. Some days, only a centimeter square could be cleaned ! Cleaning was carried out using a binocular microscope, in order to see precisely what happened under the scalpel blade and to be able to stop whenever it was necessary.

We found some new paint areas, generally rather small, sometimes buried under a rather important depth of sediment.

Example of two new painted areas on E17911, on the wig (on the left) and next to the right ear (on the right).

Example of two new painted areas on E17911, on the wig (on the left) and next to the right ear (on the right).

The biggest surprise happened with E17910 :

E17910 before and after treatment: a wig is now visible.

E17910 before and after treatment: a wig is now visible.

Close-up on the wig on the right part of E17910.

Close-up on the wig on the right part of E17910.

E17910’s face before and after, with other remains of a wig.

E17910’s face before and after, with other remains of a wig.

The cleaning allowed us to reveal a wig on the right side of E17910 and some other elements belonging to it on the face. We now know more details about the heads and they are almost able to be studied.

See you at our next post to learn more about the remaining steps of this treatment.

Fragmentary painted coffin from Abydos

If you are a member of the museum, you may have already seen some information about these painted coffin board fragments in the most recent issue of Expedition magazine:

E12505_2These fragments, which date to the Middle Kingdom (ca. 2000-1700 BCE), were excavated from the North Cemetery of Abydos in 1901 by John Garstang. The museum supported Garstang’s work through the Egypt Exploration Fund.

Despite the severe insect damage, the preservation of the painted details on these fragments is remarkable.

This fragment features 3 usekh collars, which were often reserved for nobility. Beside each collar is a mankhet, or counterpoise. The hieroglyphs above are the names of each of the collars, which are slightly different.

This fragment features 3 usekh collars, which were often reserved for nobility. Beside each collar is a mankhet, or counterpoise. The hieroglyphs above are the names of each of the collars, which are slightly different.

A detail of the usekh en nebti, the collar of the two mistresses that incorporates the uraeus and the vulture

A detail of the usekh en nebti, the collar of the two mistresses that incorporates the uraeus
and the vulture (7.5x magnification)

These coffin board fragments have never been exhibited, and our renewed interest in them is due to the fact that we are currently excavating tombs from the same time period in South Abydos, including the funerary complex of Senwosret III. You can read a lot more about this project in the recent Expedition issue and on the museum blog by following this link.

In order to exhibit the coffin fragments, they need some extensive conservation treatment. Their surfaces are dirty, the paint is cracked, cupped and lifting from the wood support, and is very fragile, and some of the boards are structurally unstable due to the extensive insect damage.

We are currently working on these boards in the lab, and we have made some good progress. We are cleaning the painted surfaces with a kneaded rubber eraser. The eraser can be shaped to a fine point, and working under the binocular microscope, it is possible to remove the dirt from most of the painted surface without disturbing the fragile paint.

We are using kneaded erasers (left) to clean the delicate painted surface of these coffin boards (right)

We are using kneaded erasers (left) to clean the delicate painted surface of these coffin boards (right)

Some areas of paint need to be stabilized before they can be cleaned. After testing a variety of adhesive solutions, I settled on my old friend methyl cellulose, a 2% solution of methyl cellulose in water to be exact, to consolidate fragile areas.

Paint consolidation is being carried out under the microscope with a fine brush

Paint consolidation is being carried out under the microscope with a fine brush

I am now working on testing some fill materials, both to stabilize the edges of lifting paint and also to stabilize the fragile wood. I will post an update as soon as I make some decisions and proceed with this part of the treatment!

 

Consolidating and reconstructing glass objects

* A new post from former Artifact Lab graduate intern Laura Galicier, contributing from a distance in Paris!

Reconstruction of a fish-shaped vessel from ancient Afghanistan (picture from a video of the British Museum, that can be viewed at https://www.britishmuseum.org/channel/exhibitions/2011/afghanistan/video_glass_blowing.aspx

Reconstruction of a fish-shaped vessel from ancient Afghanistan
- picture from a video on the British Museum website, that can be viewed by  following this link

Two glass objects from Cyprus were previously introduced to you. After an initial examination, several treatment steps were decided.

First, the surface showed evidence of delamination and was slightly flaking. We chose to consolidate the surface because if this destructive process went on it could lead to the complete loss of the object. An acrylic resin (Paraloid B72, that you’re now pretty familiar with) in acetone was chosen to do this light stabilization.

Then, we tried to see if the pieces from each object could be built up. We found that while the jug (n.63-1-196) would be able to reconstructed, the fragments of the bowl (n.63-200) didn’t fit together.

On the right: the glass jug    On the left: the glass bowl

The glass jug                                                                         The glass bowl

So the building work for the jug began! We had to find where every fragment was supposed to go. If you read our blogpost about the Egyptian Demotic jar, you’ll realize that building up a glass object is very different. Of course, the size of these glass fragments is considerably smaller than the jar fragments. Besides, the edges of a ceramic are irregular, which can help with reassembly, whereas the edges of glass are smooth.

Glass fragments glued together

Glass fragments glued together

In terms of thickness, a glass object can be very irregular, especially after deterioration, such as delamination of the surface. Generally, you hope that two fragments of similar thickness belong to the same area of the object, but with glass, delamination makes it possible for two fragments of very different thickness to fit together. Moreover, compared to ceramic, glass fragments have a very different way to adjust to each other.

Despite these differences, the methodology to reconstruct glass and ceramic has some similarities: it is necessary to map out the joins so as to know precisely where each fragment goes.

After a bit of work the fragments were put in the order to be joined.

The fragments arranged in the right order

The fragments arranged in the right order

Then, the fragments were temporarily reconstructed using scotch tape. Taping the joins clarifies where each fragment goes and exactly in which order to build them up. This order isn’t always the most obvious but if it isn’t respected, a fragment could prevent another one to fit.

The fragments were built together with scotch tape.

The fragments were built together with scotch tape.

Then, the scotch tape was removed and the fragments were glued with an adhesive (Paraloid B72). Three groups of fragments were reconstructed: fragments of the top, fragments of the bottom and a few fragments that should be placed in-between. The in-between fragments couldn’t be glued to the top or to the bottom because there’s a wide gap between them and the other fragments. This is why it was necessary to make fills so as to support these before going any further.

The three groups of fragments reconstructed and glued together.

The three groups of fragments reconstructed and glued together.

The fills will be explained in a post to come!

 

Peptide Mass Fingerprinting (PMF)

Motivated to learn more about the fur and animal hair found in our Predynastic mummy bundle, I popped up to Boston yesterday for a workshop entitled “Identifying collagen-based materials in cultural objects using peptide mass fingerprinting“.

The workshop was organized by a group at Harvard, including the Peabody Museum of Archaeology and Ethnology in collaboration with the Straus Center for Conservation at the Harvard Art Museums and the Harvard FAS Division of Science. The team received NCPTT funding for a project to develop a new application of an analytical technique called peptide mass fingerprinting (PMF).

PMF uses mass spectrometry to analyze very tiny samples of proteinaceous objects and identify the mammalian source to the species level. It actually can be used to analyze materials made of collagen and keratin, but the group at Harvard is focusing on collagen-based materials. The procedure essentially breaks up the protein into smaller peptides, and the mass of the peptides is measured using a mass spectrometer such as a MALDI-TOF. The peptide masses are compared to known reference samples, which allow for identification. This type of analysis falls under the category of proteomics, or the large-scale study of proteins, and it is sometimes referred to by this name as well.

The Harvard project is focused on applying this technique to objects made of gut, skin, sinew, and membrane from Alaska, the Northwest Coast, Northern California, and the High Plains. Another goal of the project is to bring this type of analysis, which typically takes place in large industrial or academic labs, to museum labs. You can learn more about the project on their blog.

The workshop included 3 presentations by the project’s primary analytical investigator/scientist Dr. Dan Kirby, project research associate Madeline Corona, and Kress fellow Ellen Promise. Between the 3 of them, they covered how PMF works, what it can tell you, and how it is applied to cultural artifacts, using a project on Alaskan kayaks as a case study.

After Q&A led by Peabody Museum conservator T. Rose Holdcraft, we were led on a tour of the Peabody conservation lab, where we were able to feast our eyes on some of the impressive Native Alaskan objects that they are investigating as part of the project.
A view of the Peabody Museum conservation lab, with several Native Alaskan skin and gut objects on view

A view of the Peabody Museum conservation lab, with several Native Alaskan objects on view

We also toured the impressive Mass Spectrometry and Proteomics Resource Lab, where we had a chance to see the Bruker MALDI TOF/TOF instrument and a demonstration of how samples are prepped for analysis.
The Bruker MALDI-TOF/TOF instrument and Madeline Corona demonstrating sample prep

The Bruker MALDI-TOF/TOF instrument and Madeline Corona demonstrating sample prep

The sample prep area showing the equipment used, including the MALDI plate (lower right)

The sample prep area showing the equipment used, including the MALDI plate (lower right)

Here at Penn, we are excited by this technique – not only for the minute sample size required (the samples used are just barely detectable to the naked eye) but also for its accessibility. We have a lot of animal-based materials in our collection and we are hoping to pursue using PMF to analyze these materials. Actually, we are already working to see if its possible to use this technique to identify the sources of the fur and basketry hair fibers from our Predynastic mummy, thanks to help from Smithsonian MCI fellow Caroline Solazzo, whose work focuses on keratin-based materials. PMF supposedly works on all types of samples, including those that are very old and/or are in poor condition, so we thought we’d put this to the test by starting with samples from our oldest Egyptian mummy (he’s well over 6000 years old). We will let you know how it seems to work.

A side note – a quick trip to Boston wouldn’t be complete without a stop at the Museum of Fine Arts. I spent most of my time there ogling the Ancient Egypt exhibits, admiring the massive, yet delicately decorated and inscribed coffin boards of Djehutynakht’s outer coffin (same time period and style as Ahanakht’s coffin)

The interior of the lid of Governor Djehutynakht's outer coffin (left) and detail of the false door (right)

The interior of the lid of Governor Djehutynakht’s outer coffin (left) and detail of the false door (right)

and many of the other treasures of this collection, such as this bead net dress made of faience and gold from the 4th Dynasty.
Detail of a 4th Dynasty beadnet dress (ca. 2551-2528 BCE)

Detail of a 4th Dynasty beadnet dress (ca. 2551-2528 BCE)

Breathtaking, really. I also found this shabti in a miniature coffin very charming.
Shabti of Queen Neferu with  miniature coffin, from Deir el-Bahri, tomb of Queen Neferu, 11th Dynasty (ca. 2061-2010 BCE)

Shabti of Queen Neferu with miniature coffin, from Deir el-Bahri, tomb of Queen Neferu, 11th Dynasty (ca. 2061-2010 BCE)

And while the MFA does not have conservators working in a gallery, as we are doing here at Penn, they do have some great “behind the scenes” galleries, one with interactives that engage visitors to think about conservation ethics and decision making. One of my favorites was an example using Maya Cylinder vases, examining condition issues and treatment decisions.

Some screen shots of the Maya vase example in the MFA's "behind the scenes" gallery

Some screen shots of the Maya vase example in one of the MFA’s “behind the scenes” galleries

All in all, a great trip. We’ll keep you updated on the whole peptide mass fingerprinting technique and how we might be able to use this for our collection.

 

More about our Predynastic mummy

Last year we posted some information about Bruce, our Predynastic mummy (and the oldest Egyptian mummy in the museum) here in the lab. Bruce has been on ongoing project, but he is often tucked toward the back of the lab unless we are actively working on him. While he’s often not front-and-center, when visitors enter the gallery and they catch a glimpse of him, they know that he’s special, even if they don’t know what he is, exactly.

Bruce on his cart, near the back of the lab, as viewed through the Artifact Lab windows.

Bruce, near the back of the lab, as viewed through the Artifact Lab windows.

As soon as he is spotted, I am often asked “what is that?” “is that a mummy?” and “what are you doing with him?”. In conservation, we are not always actively treating objects (or in this case, mummies); some of our projects involve close examination and study of objects (often referred to as technical studies). These technical studies may be a precursor to conservation treatment, but they may also be independent of treatment.

We are not currently carrying out conservation treatment on Bruce. Our focus at the moment is careful examination and some analysis, in consultation with other specialists. At the moment, we are focusing on trying to identify the type of animal hide that he’s wrapped in:

The red arrows are pointing out pieces of the animal skin bag wrapped around Bruce.

The red arrows are pointing out pieces of the animal skin bag wrapped around the mummy.

and also the animal hairs used to make the finely woven baskets included in his burial bundle:

E16229_basketsThese baskets are actually made of plant and animal fibers – the baskets are twined, and the passive elements (or warps) are made of plant fibers, while the active elements (wefts) are made of light and dark animal hairs. We know that the wefts are animal hairs based on our examination of these fibers using our polarized light microscope (PLM).

Views of the light-colored hair (left) and a cross-section of the hair (right) at 100X magnification

Views of the light-colored basketry fiber at 10X (upper right), at 50X (lower left), and a cross-section (lower right) at 200X magnification

Views of the darker hair (left) and a cross-section of the hair (right) at 100X magnification

Views of the darker basketry fiber at 10X (upper right), at 100 X (lower left), and a cross-section (lower right) at 200X magnification

Sometimes animal hair can be identified based on the features observed under a microscope, by comparing the unknown hairs to known reference samples. Some great animal hair ID sources on the web include this great resource on the FBI website and the Alaskan Fur ID website.

While we can clearly see that these fibers from the basket are animal hairs, we have not been able to identify them based on microscopy alone, so we are pursuing other analytical methods of identification, such as peptide mass fingerprinting (PMF). PMF uses a mass spectrometer to analyze the peptides in a proteinaceous sample, which can identify mammalian material to the species level using a micro-sized sample. Next week, I am attending a collagen identification workshop at Harvard, where I will learn more about PMF and its application to cultural artifacts.

We are excited by the possibilities this technique offers – being able to identify the skin(s) Bruce is wrapped in and the materials used to make the baskets found in his bundle will add to our understanding of very early technologies and funerary practices in Egypt. We will certainly share our findings as we learn more.

 

Back together again

Okay, I promised to write about the shabti box investigation in my next post, but before I do that, I have to share something exciting with all of you:

PUM I, our Third Intermediate Period mummy who was autopsied back in 1972, is back together again!

PUM I, before treatment in his coffin

PUM I, before treatment in his coffin

When he came into the lab, we didn’t realize how much he had been cut apart, and the extent to which his remains and linen wrappings had deteriorated. We have spent a lot of time examining this mummy, researching his history including his autopsy, cleaning the deteriorated linen and human remains, identifying and inventorying the remains (thanks to Penn undergraduate Christine Lugrine), and conserving the linen wrappings.

The conservation work on his remains is nearly complete, and he will soon leave the Artifact Lab. Come visit the lab for one last glimpse, and check out the before and after photos below.

Overall shot of PUM I before and after conservation

Overall shot of PUM I before and after conservation

View from the top of PUM I (with head removed) before and after conservation

View from the top of PUM I, with head removed, before conservation (with remains in plastic bag inside the chest cavity) and after conservation (with Ethafoam supports filling out chest cavity)

Inside the chest cavity of PUM I before and after conservation

Inside the chest cavity of PUM I before and after conservation (with Ethafoam supports)

Another view looking inside PUM I before and after conservation

Another view looking inside PUM I before and after conservation (with Ethafoam supports)

Remains removed during autopsy before and after conservation/re-housing

Remains removed during autopsy before and after conservation/re-housing