#Transformation Tuesday: New Year’s Edition

By: Céline Wachsmuth

It’s Tuesday and that means it’s time for another transformation story. This one comes from an object going into the Middle East Galleries (click here for more information on the exciting new galleries, opening this April!).

It’s hard to believe the first month of January is almost over! Many people make resolutions for the New Year, hoping to make an improvement, big or small (myself included, I have a Google doc with a list of resolutions). Most resolutions are easier said than done, including the prevalent resolution to shave a few pounds. This bowl had similar thoughts, but made losing some weight look like a piece of cake!

Bowl before treatment (left) and after treatment (right)

This bowl had been repaired in the past, but the joins needed to be taken down because the old adhesive was failing. The bowl was pretty clean when it came into the lab so it wasn’t long before I began solvent testing the adhesive in order to make a vapor chamber. The adhesive was soluble in acetone and most of the sherds separated with gentle prodding after eight days in a vapor chamber. The old fills (made of plaster), however, did not budge. This was probably due to the likelihood that they had been cast in place.

Outlines of Old Fills
Fill outlined in dark blue was dremeled out
Fills outlined in light blue were softened with deionized water and then removed

These ounces had to go! When a fill resists detachment by solvent, other, usually mechanical, methods have to be implemented. One mechanical treatment is to use a dremel, just like the one you might use at home for some smaller detailed work, to carve away the fill. This is tricky because the dremel can put the object at risk if used improperly. Once I was all set up and had been shown the proper technique, I slowly moved around the entire area of the fill.

using the dremel to remove the fill

two of the sherds sitting in a bed of glass beads while the adhesive sets

Once the large fill was removed and those ounces had been shed, it was time for some TLC. I cleaned the break edges on each sherd with acetone (for the sherds previously joined with adhesive) or deionized water (for the sherds adjacent to the old fills). All the break edges were then coated with a dilute solution of Paraloid B-72 (ethyl methacrylate methyl acrylate copolymer) and the sherds were put back together with a 50% solution of Paraloid B-72 in 1:1 acetone:ethanol. Two small areas of the bowl had some gaps that needed to be filled; one for added structural stability and one to help complete the shape. This was done using a mixture of 3M microballoons, Paraloid B-72 in 1:1 acetone:ethanol, acetone, and some dry pigment to approximately color match the fill to the bowl. The fills needed some additional color to help blend in more and they were painted with light washes of acrylics.

This bowl made losing a couple ounces look easy even though we all know how much work really has to go in to something transformative! Thankfully, it’s only the beginning of the year and there is plenty of time to make your own transformations. Just like there’s plenty of time for another transformation to happen in the labs before our next Transformation Tuesday post – stay tuned!

PS – If you’re looking for some “ancient workout tips” check out these fun suggestions

Conserving Egyptian mummies…and more

Update – this post contains outdated language. We no longer use the term “mummy” and instead use “mummified human individuals” to refer to Ancient Egyptian people whose bodies were preserved for the afterlife. To read more about this decision, follow this link.   

Recent visitors to the Artifact Lab may have noticed this new sign posted on one of the lab windows:

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Since we opened in fall 2012, you might have occasionally caught us working on non-Egyptian things, but if you visit us now, you will definitely see us working on things from other parts of the collection, especially artifacts that we are preparing for our new Middle East Galleries. Right now, we are focusing a lot of our efforts on treating ceramics and lithics, most from Iraq and Iran.

We have tens of thousands of ceramics and lithics in this museum’s collection, but somehow, in my over 4 years here, I have gotten away with working on only a handful.

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Conservator Tessa de Alarcon reconstructing a ceramic vessel. This is a common sight in our main lab (behind the scenes) but not so much in the Artifact Lab…until now.

So this is how, after spending over 4 years working on mummies and coffins, working on a small ceramic vessel becomes a novelty. And that is why I am going to walk you through some of the fairly routine steps of treating a ceramic, because I’ve never gotten a chance to write about it on this blog before, and honestly, I’m excited about it.

This small ceramic vessel with a simple striped pattern was excavated in 1931 in Ur, which is a site in modern day Iraq. It dates to the Ubaid Period, so is at least 6000 years old.

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31-17-318, before treatment (BT)

As you can see in the above BT image, it was previously broken and repaired. In order to get it ready for exhibition, those old repairs need to be removed. We don’t always remove old repairs (and we never remove repairs that date to when the objects were still in use), but based on observations of the vessel and referencing an old conservation treatment report, I knew that the repairs had to be undone –  if left in place those old materials are likely to fail and possibly cause more damage to the object. Another goal of the conservation treatment is to improve the appearance of the vessel, as there was excess adhesive and overpaint in areas and many of the joins were not well aligned.

Based on that old treatment report and tests in the lab, I knew that the old adhesive is soluble in acetone and that the material used to fill missing areas would soften in acetone enough to allow it to be removed. So the first treatment step, after documenting the piece fully, was to put it in an acetone vapor chamber:

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An acetone vapor chamber isn’t anything fancy – in this case it was created with a plastic bag. I placed the vessel and 2 small containers of acetone in the bag and then clamped the open end to prevent the acetone from leaking out. Sometimes an object only needs a few hours in a vapor chamber before it can be taken apart. This little vessel required 24 hours before even one piece could be taken off. The whole thing was finally deconstructed after a week of sitting in the chamber on-and-off and poulticing and swabbing the joins with acetone.

During treatment, after the first piece detached

During treatment, after the first piece detached

During treatment, after about half the vessel was taken down

During treatment, after more than half the vessel was taken down

Success! All the pieces are finally apart, placed on images of the vessel in order to keep track of everything.

Success! All the pieces are finally apart, placed on images of the vessel in order to keep track of everything.

Once the pieces came apart, I had to swab all the joins with acetone to remove excess adhesive and fill material. I’m now at the point where I will start joining the pieces together again.

Swabbing a break edge of a ceramic to remove excess old adhesive

Swabbing a break edge of a ceramic to remove old adhesive

Stay tuned for more posts about our work on these objects, and our continued work on the Egyptian collection and other projects!