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!

 

Update from Abydos

A few weeks ago I wrote about Penn Museum Curator Joe Wegner and his team who are currently excavating in Abydos at the mortuary complex of Pharaoh Senwosret III. Recently the team has been battling exceedingly high temperatures and consistent loss of power (so no internet and water) but despite all of this, graduate student Kevin Cahail has been kind enough to continue sending me photos and information about their latest discoveries.

Many visitors to the Artifact Lab ask if mummies are still being discovered in Egypt. The answer is yes, and now I can point to the recent discovery of a mummy just outside of one of the tombs that was recently excavated.

View of the burial chamber from tomb CS.5

View of the burial chamber from tomb CS.5

The shot above was taken after excavation of a tomb (named CS.5) – this is actually the same tomb that contained the curious bricks with the dots in them that I included images of in my last post. Excavation of this tomb revealed that the burial had been long-since removed, but soon after excavation, a skull, and then the rest of a body, was found in the sand nearby. It appears that she(?) was at some point thrown out of her tomb by robbers.

Mummy upon discovery, before excavation (left) and after excavation (right)

Exposed skull found in the sand (left). Removal of the skull revealed the rest of the body, shown here after excavation (right)

Removing and transporting unexpected or unwieldy archaeological finds often requires a bit of resourcefulness. In order to move this mummy into a box for transport back to the dig house, Kevin recovered an old laundry detergent sack, which they then slid under the mummy,

_IGP2209

and used as a sling to lift the mummy into a box.

in boxReconstruction of the skull of this mummy is now underway.

In addition to the field work, the team also spends time in the lab, which sometimes includes minor conservation work. This shabti figure was found in two pieces:

shabtiKevin used Acryloid B-72, an acrylic adhesive commonly used in conservation for repairing ceramics (among many other things) to re-adhere the fragments:

Kevin holding the recently repaired shabti figure

Kevin holding the recently repaired shabti figure

As you can see, Joe, Kevin, and the rest of the team have been busy, and they only have about another week left in the field. As I hear more from them during their last days in Abydos, I will follow up with further information.