Conservation at the Penn Museum: the next generation

Our department temporarily gained a member last week, when aspiring conservator Jessica Schwartz returned to spend an afternoon with us.

Conservator Tessa de Alarcon shows Jessica an RTI (reflectance transformation imaging) file of a seal impression from Ur.

Conservator Tessa de Alarcon shows Jessica an RTI (reflectance transformation imaging) file of a fragment of a jar stopper from Ur. The seal impression is so worn, and RTI revealed that it actually has 2 different impressions on it.

Jessie, a 6th-grader from Atlanta, has been interested in archaeology for as long as she can remember, but after seeing us working In the Artifact Lab two summers ago, she redirected her energy to pursuing archaeological conservation. There aren’t many opportunities for 12-year olds to gain experience in conservation, so we thought that if she spent some time with us, she’d get a taste of what we do on a day-to-day basis.

The first time she worked with us, last summer, we spent some time looking at our Predynastic mummy Bruce, using our microscopes to identify materials, and making scarab amulet impressions, and she wrote about all of this on the blog, which you can find by following this link.

Last week she came for a return visit (her family was here for the opening of our new exhibition, Beneath the Surface: Life, Death, & Gold in Ancient Panama) and she kept pace with all of the activities of the afternoon, including discussing my ongoing treatment of Pinahsi, a New Kingdom mummy (she had a good eye for picking out where I had repaired the textile shroud!) and reviewing radiographs of some of our animal mummies.

Jar of dirty cotton swab tips

Jar of dirty cotton swab tips

One of the first questions Jessica asked me when she came into the lab was, “what is that container full of little bits of cotton for?”. I’m so glad she asked (it’s a cotton swab disposal jar), because it gave me the idea to teach her one of the most important skills for a conservator to have – rolling your own cotton swab! We make our own swabs for cleaning objects because it allows us to have more control over the size and shape of the swab and the amount of cotton, and it’s also a lot cheaper. Jessica was so pleased with learning this new technique – I told her it would take her far!

 

Jessie with a successfully-rolled swab

Jessie with a successfully-rolled swab

After working in the Artifact Lab for a bit, we went downstairs to our new digital x-ray lab* to review some animal mummy x-radiographs. I x-rayed the animal mummies just before Jessie’s visit, so this was an opportunity for us to learn from the radiographs together. (*We are super excited about our new digital x-radiography equipment and we are just starting to use it to examine objects in our collection. I have been meaning to write a post just about the equipment and some of the things it has already allowed us to do, so look for this in the near future.)

One of the mummies we x-rayed was this ibis mummy, which our graduate intern
Alexis North treated over the summer. As far as we know, this mummy had never been x-rayed before, so we really had no idea what the radiograph would reveal. Here are the 2 views we captured:

X-ray image taken from the top down. Exposure information: 30kV, 1mA, 6 seconds

X-radiograph taken from the top down. Exposure information: 30kV, 1mA, 6 seconds. Image enhanced with flash! filter.

 

X-ray image taken from the side. Exposure information: 35 kV, 1mA, 6 seconds

X-radiograph taken from the side. Exposure information: 35 kV, 1mA, 6 seconds. Image enhanced with flash! filter.

Both views clearly show that there are bird remains inside, and the side view shows the characteristic long, curved beak of the ibis really well. The radiographs also show the textile wrappings and even the materials in the storage support! But focusing on the bird remains, they seemed a little…sparse. So we consulted with the museum’s zooarchaeologist and teaching specialist Dr. Kate Moore. She brought us into her lab and showed us a complete heron skeleton (she doesn’t have an ibis skeleton, but a heron is very comparable in terms of size and the shape of the bones).

TessaJessieKate

Dr. Kate Moore (far right) shows Tessa and Jessica a heron skeleton

Here is the complete skeleton, which Kate piled up on the table so that we could get a sense of how much volume those bones take up. After seeing these bones, we took another look at the x-radiograph, and realized that our ibis mummy only contained about half the bones of a complete skeleton (for starters, the pelvis is missing completely).

Heron bones

Heron bones with sharpie marker used for scale.

As you can see, we had a full afternoon, and we learned a lot together. Jessie had to fly back to Atlanta today to turn her attention back to her current full-time job, being a sixth grader, but we look forward to her next visit. While college, and conservation graduate school, are a bit far off in the future, we can already see that if Jessie ultimately decides to pursue conservation, she’s going to excel!

 

A different sort of unwrapping…

by Alexis North, a project conservator spending the summer working with the Buddhist Murals Project, but who also has a strong interest in Egyptian materials. Read more about her work on Egyptian objects at the Michael C. Carlos Museum, Emory University, here.

If any of you have visited the Artifact Lab in person, you may have heard us talk about how it was once popular to open or unwrap mummies, to see the body inside. Of course, this is no longer common practice, and we use non-invasive techniques such as x-radiography or CT scanning to see underneath a mummy’s wrapping without causing any damage or disturbance to the mummy’s current condition.

However, sometimes we are able to perform a slightly different kind of unwrapping, when items are found in storage in aging, opaque, or otherwise unsuitable housing conditions. Such was the case with this mystery item:

E12443, before opening and treatment

E12443, before opening and treatment

While it may look like Sunday’s dinner fresh from the butcher shop, it is actually supposed to be an ibis mummy. However, it has been wrapped in layers of tissue paper and plastic and you cannot see what the object actually looks like. While this type of storage is not damaging to the object, the fact that you cannot see the mummy inside makes this type of wrapping unsuitable. We always prefer to create storage supports or housings that allow researchers to easily see the objects without excessive handling. Therefore, this guy came up to the Artifact Lab for a little modern-day unwrapping.

E12443, after removing the plastic and tissue but before treatment

E12443, after removing the plastic and tissue but before treatment

And what a good-looking mummy it is! While we don’t have a lot of information about the age of this mummy, the intricate wrapping, which uses strips of both dyed and undyed linen, is typical of later periods in Egypt. It is also in very good condition, being just slightly dirty on the surface and having a few small areas of damage to the linen.

Detail images showing (1) a separated piece of linen wrapping on the top of the mummy, (2) a section of linen on the back torn and folded over, and (3) areas of loss which expose the ends of the woven linen underneath

Detail images showing (1) a separated piece of linen wrapping on the top of the mummy, (2) a section of linen on the back torn and folded over, and (3) areas of loss which expose the ends of the woven linen underneath

After gently cleaning the surface of the mummy using a vacuum and soft-bristled brush, I stabilized the areas of lifted or broken linen using Japanese tissue mends. Thin strips of tissue were toned brown using acrylic paint, then adhered underneath the lifting or broken areas using 2.5% methylcellulose adhesive in deionized water. I was able to reattach the broken piece of linen at the top of the mummy, and several sections of lifting wrappings which would be in danger of breaking, without stabilization.

I also humidified and reflattened the folded flap of linen on the back of the mummy. The opening caused by the folded flap was allowing fragments of the inner linen layers to break off and fall out. I used another Japanese tissue mend with methylcellulose to hold the reshaped flap in place.

Before (left) and after (right) flattening and readhering the flap of linen on the back of the ibis mummy

Before (left) and after (right) flattening and readhering the flap of linen on the back of the ibis mummy

Here are some images of the ibis mummy after I completed its treatment. I know it doesn’t look very different, and that happens a lot when treating archaeological objects. My goal wasn’t to improve or restore the mummy in any way, just make sure it could be safely handled and stored without any further damage.

    Images of (1) the top of the mummy, (2) the proper right side of the mummy, and (3) a detail of the reattached linen strip, after treatment

Images of (1) the top of the mummy, (2) the proper right side of the mummy, and (3) a detail of the reattached linen strip, after treatment

My last step was to make a new storage tray so the mummy can be easily seen and examined, without any wrappings besides the ones it came with!

The ibis mummy in its new storage mount

The ibis mummy in its new storage mount

 

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!