A closer look at our stola coffin lid

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

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.

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.

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.

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.

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.

L-55-16B_detail7

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.

 

Exploring the painted surface of three coffin fragments

Last week, I wrote about x-raying the fragments of a painted wooden coffin, as part of the conservation treatment. The radiographs helped us see what is under the painted surface. We then turned to the painted surface itself. Through cleaning, we revealed how beautiful and well-preserved the decoration is. I described the cleaning process (and linked to a short video showing the process!) in a previous post.

E12617beforeaftercleaning

E12617A-C coffin fragments before (left) and after (right) cleaning

While it was impossible to see the full range of colors on the boards before cleaning, after cleaning we could see that there were several different colors used to decorate the surface, including two different yellows, red, green, black, and paint that appears black but where it is abraded/damaged looks blue. After much experience working on ancient Egyptian painted wooden artifacts, I knew enough to suspect that some of the paint that appears black is actually Egyptian blue.

It appears that there is a lot of black paint here, but not all of this paint was originally black. The yellow arrows point to black paint while the red arrows point to areas that I believe were originally blue.

It appears that there is a lot of black paint here, but not all of this paint was originally black. The yellow arrows point to black paint while the red arrows point to areas that were originally blue.

If you’ve been reading our blog, you are probably very familiar with one of our favorite photography techniques for Egyptian material, visible-induced infrared luminescence imaging. I have written about it previously, where I explain the process and the equipment we use (follow this link to the post).

Sure enough, it worked beautifully to confirm, and to allow us to see the Egyptian blue on this object:

E12617normaIRfalsecolor

Image of the coffin boards in normal light (left), Visible-induced infrared luminescence image (center), False color image (right). Click on the image to see a full-screen version.

All of the darkened/altered Egyptian blue shows up as bright white in the center image above, and the red areas in the false color image on the right help to further visualize where the blue is in relation to the rest of the painted design. Gotta love this technique!

So that’s great for determining the presence and location of Egyptian blue. But what about some of the other colors? I was particularly curious about the two different yellows and the green. In the case of the yellows, are they two different pigments? And as for the green, which pigment(s) were used to produce this color? Without (for the moment – more about that later) knowing the exact time period of this object, I knew there could be at least a couple different options, including Egyptian green (or green frit), and green earth.

To gather more information about these pigments, I carried out portable x-ray fluorescence analysis (pXRF) in select areas on the boards. I collected data from the following areas, marked with colored X’s in the image below:

pXRF analysis locations, with elements detected listed in order of peak height, from large to small

pXRF analysis locations, with elements detected listed in order of relative peak height, from large to small

As you can see, I labeled the image with the findings from the pXRF analysis. It looks like the two different yellows are indeed two different pigments: the darker, more orange-yellow paint contains primarily calcium and iron, suggesting that this is an ochre, while the brighter yellow paint contains calcium, arsenic, and iron. The relatively large amount of arsenic suggests that this yellow was produced using orpiment (arsenic sulfide).

The green paint also contains arsenic, as well as calcium, copper, and iron. So it appears that the green was produced by mixing an arsenic-containing material (orpiment?) with a copper-containing pigment. Due to the lack of any visible-induced IR luminescence in the green areas, I don’t think that these areas could contain any Egyptian blue, so perhaps the green was made by mixing orpiment with Egyptian green. And as you can see, the blue paint does not contain any arsenic, but does contain calcium, copper, and iron, which we expect to find in areas painted with Egyptian blue. Further analysis will be necessary to determine exactly which pigments were used in the yellow and green areas, but we have discovered a lot using these completely non-invasive techniques!

In my next post about this object, I hope to write about the translation and interpretation, for which I’ll need to consult with the museum’s Egyptologists. In the meantime, if you’d like to learn more about green pigments on ancient Egyptian objects, and more applications of multispectral imaging on Egyptian objects, check out this really great video presentation by Kelsey Museum Conservator Carrie Roberts (originally presented at the 2014 ASOR Annual Meeting):

Green Pigments: Exploring Changing in the Egyptian Pigment Palette from the Late to Roman Periods through Multispectral Imaging and Technical Analysis

X-raying fragments of a painted wooden coffin

I recently completed the treatment of these coffin board fragments.

E12617A-C, boards from a painted wooden coffin, before treatment

E12617A-C, boards from a painted wooden coffin, before treatment

In addition to the cleaning, which I blogged about before, the treatment involved stabilization of loose and powdery gesso and paint, filling losses where needed for structural support, and x-radiography, multispectral imaging, and portable X-ray fluorescence (pXRF) analysis. It has also enabled a translation of the text. I’m going to write a few shorter posts to highlight the different components of this project, starting with the x-radiography.

During my initial examination of the boards, I could see that the boards represent just a portion of the front, head end of the coffin. The rest of this side of the coffin would have continued much further to the left, but at some point these pieces were cut down and finished off on the left side to a smooth edge. This is most evident when you look at the hieroglyphic text, which obviously should continue to the left.

I could see that these 3 boards were originally joined with wooden dowels, because there are wooden dowels protruding from the join edges. I also noted some large cracks in the painted surface of the largest (center) piece in the image above, which led me to realize that this central piece was made of more than 1 piece of wood. I turned to x-radiography to get a better understanding of what is going on below the surface.

Here is a composite image showing the radiographs of the 3 boards:

E12617A-C x-ray image

E12617A-C x-ray image

The dowels joining the 3 pieces together are very clear in the x-ray image above. There are some darker (almost black) areas, which represent the holes that were drilled out for inserting the dowels. The denser (whiter) areas within those voids are the wooden dowels themselves. I’ve outlined these areas in green in the image below.

E12617xraymapped-1The x-ray image also helps clarify how the center piece is constructed, with 3 pieces of wood, which I’ve outlined in red above. Where those 3 pieces of wood join correspond directly with the cracks observed in the painted surface on the exterior.

Also visible in the x-ray image are two small nails driven into the lower edge of the bottom board. These nails are historic additions, likely added at the time when the boards were cut down and modified, although their purpose is unknown.

In my next post, I’ll focus on what cleaning, pXRF, and multispectral imaging has revealed about the painted surface, and I’ll include some after-treatment images.

 

Observations of a stola coffin lid

As if there is not enough up here (see our recent post about the Egyptian storage move and associated conservation work), this week we brought another quite large object into the lab, and it might be my new favorite object up here.

The lid of our yellow stola coffin

The lid of our* yellow stola coffin

This is the lid that belongs to the late 21st/22nd Dynasty yellow coffin base which we recently treated here in the Artifact Lab. Due to its previous location in storage, I hadn’t been able to take a close look at it until this week. Now that I’ve gotten to spend a few days with the lid, I’ll tell you that it’s total eye candy. If you were impressed by the painted decoration on the base, the lid will give you even more to get excited about.

I only just started to examine and document the lid and I will continue to update the blog as I work on this object, so today I’m just going to mention a few things about it, and some of my favorite details so far.

First of all, you may have noticed that I referred to this as a “stola” coffin in the image caption above. The term “stola” refers to the narrow red band depicted on the coffin that encircles the neck and crosses over the chest and over the oversize collar. Both the presence of the stola and the oversize collar have been recognized as distinctive of the late 21st/early 22nd Dynasty (see other examples and explanations here and here, and special thanks to Dr. Kara Cooney at UCLA for information as well).

The figure depicted on this coffin used to have a beard, which is now missing, but there is a hole in the chin indicating that it was once there.

Detail of the hole in the chin

Detail of the hole in the chin

The arms are depicted as being crossed over the chest and the hands are made of separate pieces of wood. The hands on this coffin are clenched and I have read that this is reserved for male coffins while females are depicted with hands open and lying on their chests. I’m assuming the fisted hands mean that this coffin belonged to a man, but I’ll have to check with our Egyptologists to confirm, since I cannot translate any of the text myself. I also really like the fact that the thumbnails are painted in:

Detail of the left hand

Detail of the left hand and thumb

What else can I say about it? Well, it is beautifully painted and also varnished just like the base with a yellow-colored pistacia resin. This pistacia resin causes many of the areas painted blue to appear green:

Much of the blue lines on the wig appear green, but in areas where there is no varnish, you can see the blue color of the paint.

Many of the lines on the wig appear green, but in areas where there is no varnish you can see the blue color of the paint.

There is a thick layer of dust on the surface of the coffin, but I can tell it’s going to clean up well. Check out the embossed details in this raking light image, which were built up with gesso:

Detail of the embossed designs on the central part of the lid

Detail of the embossed designs on the central part of the lid

This is going to be a fun object to work on! I’m looking forward to getting started with the treatment.

* I should clarify that this coffin technically belongs to the Philadelphia Museum of Art (PMA) but has been on long-term loan to us for nearly a century. We received this coffin as part of an exchange of objects between our 2 institutions in the 1930s. I am carrying out the treatment in close consultation with the conservators at the PMA.

Treasures from Egyptian storage

If you have visited the Artifact Lab in the last couple weeks, you may have noticed that we have a few more objects out than usual, and often, an additional conservator working in here.

A few objects that were brought to the Artifact Lab recently for conservation treatment before they are moved off-site.

A few objects (stone, cartonnage, ceramics) that were brought to the Artifact Lab recently for conservation treatment before they are moved off-site.

The new objects were recently brought up from Egyptian storage by conservator Alexis North, who was previously here as a graduate intern, and now is working as the new Project Conservator for the inventory and move of our Egyptian collections to an off-site facility.

Due to construction that will be happening at the Hospital of the University of Pennsylvania (HUP), which is adjacent to the museum, certain storerooms and galleries will be affected and as a result, the entire Egyptian collection in storage (with some exceptions) must be moved off-site for the duration of the project. This move requires a new inventory of the collection and also that everything be examined and stabilized, through conservation treatment and/or packing solutions, which will benefit the collection greatly. In addition, emptying the Egyptian storerooms will allow us to carry out a much-needed renovation of these areas, so that when the collections return, they will be housed in a much better protective environment.

We will try to feature some of the more interesting objects that come up to the lab as a part of this project on the blog, but if you do have a chance to stop by the Artifact lab this summer, you’ll be in for a treat, I assure you, because we will be working on some pretty amazing things.

This faience beaded collar is just one of the beautiful beaded objects that came into the lab recently as part of the move project.

This faience beaded collar is just one of the beautiful beaded objects that came into the lab recently as part of the move project.

 

The treatment of (half of) a yellow coffin

This week, we finally finished the treatment of the lower half of our 21st/early 22nd Dynasty yellow coffin.

A view of the interior of the coffin before (left) and after (right) conservation treatment.

A view of the interior of the coffin before (left) and after (right) conservation treatment.

The treatment mostly involved cleaning the interior surfaces to remove dust using a soft brush and HEPA-filtered vacuum, and cosmetic sponges. Here’s another view to give you a better sense of just how much grime had accumulated in the interior of the coffin:

A detail of the head of the interior of the coffin before (left) and after (right) conservation treatment.

A detail of the head of the interior of the coffin before (left) and after (right) conservation treatment.

There was also a fair amount of flaking and lifting paint, which needed to be stabilized. We used 1-2% methylcellulose in 50:50 water/ethanol to consolidate flaking paint, and Japanese tissue paper and 5% methylcellulose to fill gaps.

In the course of the treatment, I have also continued to research the significance of the holes drilled into the bottom of the coffin, which can clearly be seen in the overall images at the top of this post, but here is another look:

An overall shot of the coffin bottom, with a detail of 4 of the holes below.

An overall shot of the coffin bottom, with a detail of 4 of the holes.

I’m anxious to start working on the lid of this coffin, which will inevitably provide more information about this object and it’s history. We should be able to bring the lid from storage up to the lab sometime this summer, and I’ll post images of it as soon as it arrives. In the meantime, I have enjoyed researching these types of coffins and finding images of similar ones in other collections (like this one at the Petrie Museum, this one at the Houston Museum of Natural Science, and this “remuddled” coffin at Stanford University) which is helping me gain a better understanding of these coffins and the contexts in which they were made.

Looking inside Nespekashuti

A few weeks ago I introduced you to Nespekashuti, a New Kingdom mummified man who we recently removed from display in our mummy room for conservation treatment. Even though we’ve had Nespekashuti and his coffin since 1893, we have very little information in our database about him. Working on his remains in the Artifact Lab is providing an opportunity to take a much closer look and to learn more about him.

Overall view of Nespekashuti before treatment

Overall view of Nespekashuti before treatment

One of the first things we decided to do was to x-ray his remains using our new digital radiography equipment. Although Nespekashuti looks pretty well-wrapped (despite his teeth being exposed), this is what we see under the wrappings:

X-ray of Nespekashuti (image created by stitching several x-rays together)

X-ray of Nespekashuti (image created by stitching several radiographs together)

As you can see, there are some big empty spaces (areas that are completely black), especially the neck and upper chest area, and there are areas where bones are completely disarticulated and appear to be piled on top of each other. We’re not really sure why this would be, but we have some ideas. Dr. Janet Monge, our physical anthropologist, is currently taking a closer look at the x-ray images in order to draw some conclusions about the bones and their condition, which may help us better understand why they are a bit of a jumbled mess…not unlike another mummy we recently treated and x-rayed, Pinahsi.

In the meantime, I’ve started the conservation treatment, which I’ll be sure to report on as I make progress.

A tiny mystery mummy

Yesterday we x-rayed mummies of 2 extremes: a full-sized human mummy (Nespekashuti), and a tiny mystery mummy:

mystery mummy

This tiny mummy is about 2″ wide and 5″ long, and easily fits into one of my hands.

We already had the x-ray tube warmed up for capturing images of Nespekashuti, so we figured we’d zap this little mummy while we were at it, to find out what is underneath those wrappings. We had lots of guesses, but ultimately, none of us guessed correctly.

Here is one of the x-ray images:

An x-ray image of our tiny mystery mummy

An x-ray image of our tiny mystery mummy

We had 3 conservators in the room when this image popped up on the computer screen, and we were immediately puzzled. Bird? Definitely not. Crocodile? No. Mouse? Nope. Cat? Again, a no. Could it be a…dog? We knew that the 3 of us non-experts couldn’t say anything with any certainly, so we called in the big guns…in the form of zooarchaeologist Dr. Kate Moore, who has helped us with some of our other animal mummies in the past.

Dr. Moore spent some time looking at the images, and then looking at some x-ray images of immature dogs (puppies!). She was troubled by a few things, including the fact that we can’t see any teeth and that the animal appears to have only 1 leg, also the length of the spine and front paws/feet, but ultimately concluded, based on the x-ray images that we captured, that this is indeed a puppy, who died right around the time it was born.

Based on its size, I don’t think any of us expected this tiny mummy to contain a dog, but it’s not surprising that we would have a dog mummy in our collection, since millions have been found in Egypt, notably in the Dog Catacombs of Saqqara. And this isn’t the only puppy mummy in our collection – if you visit the museum, you can see Hapi-puppy on exhibit, displayed at the feet of his owner, Hapi-men, both of which have been CT-scanned. A CT-scan of our newly-discovered puppy mummy would provide greater detail and a better understanding of this tiny animal, and would help make a more certain identification. We’ll be sure to update the blog with any new findings if we are able to do some more imaging.

 

Wilfred/a’s many mysteries

Last week, we moved our mummy Wilfred/a from the Artifact Lab down to our new digital x-ray lab to capture some x-ray images and hopefully get to the bottom of the male/female debate.

Wilfreda after treatment

Wilfred/a after treatment

Above is an overall after treatment image of Wilfred/a. The goal of the treatment was to get this mummy out of the original packing materials, to assess and document the remains, and to house them in a way that they can safely be moved to our x-ray room for imaging, and then returned to storage. If plans are made to exhibit Wilfred/a in the future, further treatment can be carried out at that point, but for now, this mummy is stabilized and will be much more accessible for research.

We were excited to x-ray Wilfred/a’s remains, but while we are used to x-raying ceramics, wooden artifacts, metals, and other types of cultural materials, x-raying human remains is not something that any of us in the conservation department specialize in, so we brought in some experts to help us with this task: Dr. Janet Monge, Keeper and Curator-in-Charge of the Museum’s Physical Anthropology Section, and Dr. Morrie Kricun, Emeritus Professor of Radiology, Hospital of the University of Pennsylvania. In fact, it was Dr. Monge and Dr. Kricun’s initial examination of Wilfred/a’s remains and some old 1932 x-ray radiographs that made us think that this mummy may be female, rather than male.

With the assistance of Dr. Monge and Dr. Kricun, Conservator Tessa de Alarcon and I captured a complete sets of x-ray images of Wilfred/a. And the really cool thing about having a digital system is that we can capture the images in seconds, and see the results immediately. While full interpretation of the images is underway, I will share a couple of the findings that are quite interesting.

First, let’s clear up the debate and start addressing this mummy by the appropriate pronoun. This mummy is female, and therefore we’ll call her Wilfreda from now on (or until someone proposes a new, more appropriate name). Determining that Wilfreda is female was possible by a thorough examination of her pelvis. There are a few other possibly very cool findings related to the fact that she’s female, but I’m going to wait on the full interpretation before sharing any other details about this on the blog.

Secondly, we knew that Wilfreda’s head was missing, but what we didn’t realize was this:

wilfredanofeet

X-ray radiograph of Wilfreda’s lower legs and (missing) feet. Exposure: 65kv 5ma 6 seconds

Her feet are missing! From the outside, it is obvious that the wrappings around the feet were disturbed at some point, but it wasn’t possible to see until these x-rays were taken that the feet are totally gone. In this next image, which we captured to better see the linen wrappings, you can clearly see where the feet would have been:

45kV 5ma 6 seconds

Exposure: 45kv 5ma 6 seconds

The weird thing about this is that her feet were there when the 1932 x-rays were taken:

wilfredaoldxrays

2 different x-ray images captured in 1932, clearly showing the feet of the mummy.

Where have her feet gone? We don’t know. This is now a new mystery.

Just in case any of you are following this blog very closely, and are wondering if the feet could have been lost somewhere inside the old crate (pictured below), the answer is no, but some other things of interest did turn up in there.

wilfredascrate

Buried in the old padding of the crate, we found the following:

Wilfredasbox

  • a Keuffel & Esser Co. 1903 Catalog of drawing materials and surveying instruments
  • 4 tickets that say: “Only for School Children – Not Transferable. Barakat’s Lecture, on BIBLE LANDS, illustrated by ancient curiosities used 1800 years ago, and costumes worn 4000 years ago. ADMIT ____ who will Bring this and Five cents.” (I’ve neglected to write about him on the blog but Wilfreda was originally in the possession of Professor Elias Barakat, who, for about a decade, traveled around the US lecturing about the ancient world, with Wilfreda as one of his “curiosities.” His wife donated Wilfreda to the museum in 1911.)
  • Rubber stamps, for printing announcements, etc., one of them with Barakat’s name
  • small wooden dowels
  • a piece of cartonnage
  • fragments of wood, textile, paper, plant materials, seeds.

Leave it to Wilfreda to keep a few surprises from us. We’ll post more about the x-ray interpretations once we know more, and continue to try to put the pieces of these mysteries together.

A closer look at one of our feathered friends

We have an ibis mummy in the lab, which is revealing itself to us in an unusual way.

Unlike most animal mummies in our collection, we can actually see the ibis’ remains – in this case, its feathers! It is unfortunate that the linen wrappings were damaged in the past, but this damage does provide a unique look under the bandages.

ibiswithfeathers

Ibis mummy, 97-121-19, from Thebes, Late Period (ca. 664-332 BCE).

While x-ray radiography revealed that there is indeed an ibis inside (the beak is a dead giveaway), the feathers provide further clues about this bird that was mummified approximately 2500 years ago.

Radiograph taken from the top down. Exposure information: 35kV, 5mA, 6 seconds. Image enhanced with flash! filter.

Radiograph taken from the top down. Exposure information: 35kV, 5mA, 6 seconds. Image enhanced with flash! filter.

When researching ibis mummies, I read again and again about the African Sacred ibis (Threskiornis aethiopicus) being mummified, but there were other types of ibis in Egypt, including the Glossy ibis (Plegadis falcinellus) and the Northern Bald ibis (Geronticus eremita). I don’t know if evidence has been found that these other types of ibis were mummified, but I do know that I shouldn’t immediately assume that this particular ibis mummy contains the remains of an African Sacred ibis.

So, let’s look at the feathers, and what we can learn from them. The feathers that are exposed appear to be contour feathers that may be part of one of the wings. There are a few completely detached feather fragments in this area, so I was able to take a closer look at one small fragment under the microscope.

ibisfeatherlabeled

Left: ibis feather 7.5X magnification. Right: ibis feather 50X magnification.

The most obvious feature to note, even without a microscope, is the coloration. This feather is white and black. The African Sacred ibis has a very beautiful, distinctive, black and white plumage, so in this case the color alone may be enough to identify species.

If we can’t rely on color, what else can we learn from this feather fragment? Well, we can see that it is part of a pennaceous (rather than plumulaceous, or downy) feather, the parts of which I’ve labeled in the above images. To take an even closer look at these elements, I used our polarizing light microscope and was able to see the tiny hooklets on the barbules, which “zip” the barbules, and therefore the barbs, together.

Ibis feather 100X magnification.

Ibis feather 100X magnification.

The barbules of feathers can be used for identification of species, but usually barbules from plumulaceous feathers are used, as they have a very different and distinct appearance. Unfortunately, I don’t have access to any plumulaceous feathers from this ibis mummy, so this may be as far as I can go at the moment. There are other researchers, both within the field of Egyptology, but mostly in ornithology, who have spent much more time looking at ibis feather structure than I have, and of course there is DNA research, so we may learn more in the future about this ibis mummy and its feathers.

I have a special place in my heart for birds and feathers, since before coming to the Penn Museum, I worked on an extensive project on feather coloration as part of a collaborative research effort between UCLA and the Getty Conservation Institute. Click on the links below to find out more about this work:

A Collaborative Study of California Featherwork

California Featherwork: Considerations for Examination and Preservation

And to learn more about feather structure, start by following this link: The Cornell Lab of Ornithology: All About Birds: Feather Structure