What do the conservators do when they’re not in the Artifact Lab?

Posted on November 23, 2012 by artifactlab

Molly Gleeson, the primary project conservator for the Artifact Lab is on vacation so, if you come by over the next little while, one of the other staff conservators (Julie Lawson, Nina Owczarek and I – Lynn Grant) will be taking turns being the Conservator on Duty. While there, we work on the same sorts of projects that Molly does but you might wonder what we do when it’s not our turn in the fishbowl. With a collection of over a million artifacts, there’s plenty to keep three (or even 30, if we just had room) busy. Because Penn Museum’s collections are so large, we have to prioritize what we work on. The conservation treatments we’re working on right now are mostly for objects going on exhibition (mainly Native American artifacts for an exhibition opening in a year), or on loan (we loan artifacts to Museums all over the world; this fall we’ve worked on objects going to New York, Indianapolis, Cleveland, Spain, Amsterdam, Switzerland, and Taiwan, to name just a few) or artifacts being photographed for publication.

One of the places conservator Lynn Grant spent time recently: an art storage warehouse in Connecticut where some of our collections were stored (white crates).

In addition, we work very closely with other Museum staff on preventative conservation (see Molly’s earlier blog post, to keep our collections in the best possible condition. This means monitoring storage conditions, artifacts on exhibition, advising on materials used in display, and many other tasks. These don’t always happen in the Museum, either. We conservators often act as couriers, accompanying artifacts as they travel to make sure that they receive the proper care. One recent courier trip I did has a certain amount of overlap with work in the Artifact lab, since it involved an Ancient Egyptian tomb chapel.

One block (the false door) from the offering chapel of Kapure. This single limestone block weighs over 9000 pounds.

The late Old Kingdom offering chapel of Kapure from Saqqara (dating to ca. 2300 B.C.) was once part of this high ranking official’s mudbrick mastaba tomb. The interior of the chapel was lined with limestone blocks beautifully decorated with carved and painted scenes representing the deceased seated at a table of offerings and receiving funerary provisions. Part of the chapel of Kapure is on display in the Museum’s Lower Egyptian Gallery. The rest, which was part of a traveling exhibition in the late 1990s, has been in storage in Connecticut since 2000. This was supposed to be a temporary situation but it’s gone on for longer than we ever expected and now that there is a suitable storage facility here in Philadelphia, we decided to bring the tomb chapel closer to home. Why wouldn’t we just bring it back to the Museum, you ask? Well, it’s kind of big and very unwieldy. There were 8 crates, the heaviest of which weighed over 9000 lbs. We hope to be able to reinstall it in our Egyptian Galleries before too much longer but until then, it will stay in specialized art storage.

My colleagues in adventure, Bob Thurlow (left) and Jen Wegner, get ready to to work on our crated limestone blocks.

Getting it there was a bit of an adventure. Three Museum staff members: Bob Thurlow of the Registrar’s Office, Dr. Jen Wegner of the Egyptian Section, and myself, traveled to the warehouse where it was stored in Connecticut. There we had to open each crate; document the current condition of the blocks inside both with digital photography and written descriptions; check that the crates were still in good enough condition to protect the artifacts during transit; make any necessary improvements to the crates; then oversee the loading of the crates on to a very large truck; follow the truck to the new warehouse; and finally supervise the unloading and placement of the crates there. This all took two-and-a-half days and meant long hours working in an unheated warehouse – in November.

Art handlers and warehouse men load the false door crate on to the truck, using the big forklift (the smaller one couldn’t lift the 9000 lb weight). The crate fit with about 2 inches to spare – a tribute to Bob Thurlow’s excellent planning and preparation.

Jen Wegner explaining the finer points of the false door block to two of the warehouse employees just before we put the lid back on and prepared to take it back to Philadelphia.

This is not the glamorous part of our jobs! Still, it needed to be done and it was a great chance to get up close and personal with some gorgeous Egyptian funerary art. Working with Jen Wegner was a treat as she was able to tell us what we were looking at and read the inscriptions. I’m sure Jen got tired of me asking what various symbols were, especially since most of them seemed to be bread – apparently Egyptian funerals were a carb-fest!

posted by Lynn Grant

Ask the conservator!

Posted on November 20, 2012 by mollygleeson

Since the Artifact Lab opened on September 30, we (meaning my fellow Penn Museum conservators and myself) have spoken to hundreds of people who have visited the exhibit during our open hours (Tues-Fri @ 11:15am and 2:00pm, Sat-Sun @ 1:00pm and 3:30pm). Being the full-time conservator in the Artifact Lab, I get to talk to lots of our visitors, and I have to say that it has been one of the most fun parts of my job.

Chatting with visitors during a Q&A time in the Artifact Lab

I particularly love it when people ask me questions. Many of these questions are about Egypt-and because I am not an Egyptologist, I have spent a bit of time looking things up, asking our curators, and often saying “I don’t know, but I’ll see what I can find out.” We try to post answers to some of the frequently asked questions here on our blog, and we encourage you to ask questions via this blog well, by leaving them at the end of any of our posts, or in the comments box at the end of the FAQs page.

But many questions are about conservation, and this is an area that I can talk a LOT more about. One conservation-related question that I have heard a lot lately is “what are you going to use to repair that object, and will you use the same materials as the original?”. This is a great question, and gives me the opportunity to talk a bit about conservation decision-making and ethics.

There is a lot to consider when making decisions about how to repair objects and what materials to use. No two objects are exactly alike, so what works for one object may not work for another that is very similar.

One of the first things to consider is the nature of the object-what is it made out of and what is its condition (and why does it need conservation treatment)? We are always looking to choose treatment materials that are compatible with the original materials of the object and that will provide the strength, cohesion, etc. that the object needs.

That being said, we also use materials and methods for treatment that make our work easily distinguishable from the original object. For example, many conservation treatments involve filling losses in objects with new materials and coloring the fills to blend with the surrounding original materials. When carrying out this work, many conservators use an approach known as the rule of “6 Feet, 6 Inches”-meaning that when an object is viewed at 6 feet the repair is not visible but at 6 inches it is easy to distinguish from the original. We also document all of our treatments thoroughly in written reports and photographs, so that in the future it will be clear what has been done.

Another factor when choosing treatment materials is their long-term aging properties-we don’t want to use anything that discolors or becomes brittle over time (such as Duco cement) or will be very difficult, if not impossible, to remove later (like Elmer’s glue!!).

There is a LOT more to say on this topic, and as we put up new posts about ongoing projects we we will try to include information about the decision-making process. In the meantime-Ask the Conservator! Let us know if you have a question-either come visit us during our open window times or leave us a question here!

pXRF follow-up

Posted on November 9, 2012 by mollygleeson

A couple weeks ago we brought out our portable X-ray fluorescence (pXRF) analyzer to aid in our study of some of the objects in the Artifact Lab. We provided an overview of this session earlier on our blog-read more by clicking here.

One of the objects that we looked at with the pXRF is this painted wooden coffin. I also wrote a blogpost about this artifact and you can read more about it there.

Painted wooden coffin of Tawahibre

A critical part of the conservation process is examining and documenting objects-their materials, technology, and condition-all of this information is recorded in condition/treatment reports. Beyond saying that this coffin was decorated with red, yellow, white, black, and blue paint, we would like to provide more information in our report about which pigments were used, if possible. Based on knowledge of the painting materials used in ancient Egypt, we had some ideas, and we were hoping that the pXRF could confirm that our ideas were on the right track.

One pigment we were interested in knowing about is the blue. Here is a detail of the blue paint in one area:

Detail of coffin, showing blue paint

Considering that Egyptian blue was the principal blue pigment used in ancient Egypt, this was our first guess. Egyptian blue is a synthetic pigment, one of the first synthetic pigments ever produced, made by heating together copper, silica (sand), lime (calcium oxide) and an alkali such as natron (sodium sesquicarbonate). This pigment is found on objects from as early as the 4th Dynasty through to the Roman Period. The hue varies from dark to light blue, depending on the components and the grinding process (or the final particle size). Dark blue colors tends to have a larger particle size and smaller particles produce a lighter blue.

So how can the pXRF help us understand what blue pigment was used on this coffin? Well, as previously described, XRF is useful for identifying elements present in a sample or targeted area of an object. We simply positioned the pXRF in contact with the area of interest, in this case, a stable area of the blue paint, and took a reading.

The pXRF analyzer positioned in contact with the target area of interest

The reading produced a spectrum with peaks representing the x-ray energies of the elements present.

pXRF spectrum of the blue paint from the coffin

Here we have labeled the peaks of each element detected-you can see that there are very high peaks for Calcium and Copper. This is what we would expect to see for an Egyptian blue pigment!

We’re looking forward to continuing to use this technique for examining other objects in the Artifact Lab-especially those artifacts with only traces of paint left or those objects with surfaces that have darkened and where the original colors are more difficult to interpret. We’ll continue to update the blog with this information as we find out more.

Is that…real??

Posted on November 4, 2012 by mollygleeson

One of the most common questions we get asked in the Artifact Lab is, “is that … real?”.

And our answer is always, yes. Everything that we’re working on in the Artifact Lab is indeed real, and from ancient Egypt. Objects in the lab right now range from between 4000-2000 years old and many were excavated and came into the Penn Museum collection over 100 years ago.

Collecting Egyptian materials was of great interest to the Penn Museum from the very beginning, when it was founded in 1889. The Egyptian and Mediterranean Section was created a year later, and Sara Yorke Stevenson was named the first curator of this section-she was also the first female curator of an Egyptian collection in the US! Her goal was to build this collection quickly and through excavation as much as possible, and objects came into the collection through expeditions funded by the museum, including projects run by Sir William M. Flinders Petrie. Because so many objects were acquired in this way, we can be sure of their authenticity and provenience.

In a few months, however, we will have to modify our answer to the “is it real?” question slightly. There is one object currently on display that will soon be replaced with a replica.

A painted linen mummy shroud currently on display In the Artifact Lab.

This painted linen mummy shroud is now on display In the Artifact Lab. Due to its sensitivity to light, it can only be safely displayed for 3 months at very low light levels. After this time, a replica of the shroud will take its place.

The control of light exposure is an important part of any preventive conservation program. Preventive conservation refers to actions taken to minimize the rate of deterioration of collections and objects, and this includes managing the museum environment, including temperature, relative humidity, light, and pests. To prevent or reduce light damage, many museums have an exhibition lighting policy, which provides guidelines for the allowable light levels and cumulative light exposure for objects based on their light sensitivity (textiles for instance are more sensitive to light than stone objects).

While we will have many interesting things to see throughout the duration of this exhibit, now is the chance to come and see this incredible funerary shroud-the real thing-before it is returned to storage to prevent light damage.