stola coffin | In the Artifact Lab

For the past few weeks, it has been full steam ahead on the treatment of the stola coffin lid. The lid is made of smaller pieces of wood joined together, then covered generously in areas with a thick layer of coarse mud plaster, followed by a thin layer of a finer mud plaster, followed by paint and a varnish. There are also raised details that were built up with gesso before painting.

This large piece of painted mud plaster (detached from the foot of the coffin, seeing on the left) is 11 cm thick.

This large piece of painted mud plaster (detached from the foot of the coffin, seen on the left) is 11 cm thick.

This area of damage clearly shows the wood substrate (green arrow), coarse mud plaster (blue arrow), and finer mud plaster (red arrow).

The two major condition problems on the coffin are found in the mud plaster layers: the coarse mud plaster has lost cohesion and in many places has separated from the wood below, and the finer mud plaster has also lost cohesion, so much so that it has deteriorated to a fine powder in places. I have spent over 150 hours so far readhering detached plaster, consolidating the powdery plaster, and realigning and stabilizing loose fragments on the coffin. Today I’m posting a few before and after treatment details to show the progress.

Here are before and after details of the top of the head showing an area where I had to readhere some large fragments of painted plaster:

Top of the head before (left), during (center), and after (right) reattaching painted plaster fragments

Here are before and after details of the left eye showing the consolidation of exposed powdery mud plaster:

Detail of losses near the left eye before, showing powdery mud plaster (left) and after cleaning and consolidation of the mud plaster in the losses (right)

And here is an area on the side of the head where I found that some fragments were previously attached in incorrect places. They were repaired long ago (with no documentation) with an adhesive that is soluble in warm water. I reversed the old repairs and found the correct locations for the fragments. I’ve outlined the fragments in their incorrect locations in the before treatment image on the right, below:

Detail of treatment on the side of the head before, with misplaced fragments outlined in pink (left), and after respositioning (right)

I still have lots of work to do before the treatment is complete, but I’m making good progress! I hope to be finished with the treatment early in the new year.

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.

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.

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 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.

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.

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.

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.

In the Artifact Lab

Tag Archives: stola coffin

Progress update on the stola coffin treatment

A closer look at our stola coffin lid