Tales from the Bench
RAMM’s conservators and mountmakers prepare many different kinds of objects for the museum. These tales from the bench tell you about what they are working on in the laboratories at the moment. We’ll add more information and new tales as conservation work progresses.
When I first inspected the 15th century Tyrolese Annunciation altarpiece in 2005, it was in such a deteriorated condition that I was scared my breath might dislodge the paint. Piles of paint fragments and exposed stretches of bare wood showing evidence of attack by death-watch beetle, indicated the urgent need for conservation. Cleaning tests alongside paint analysis soon established that there was a medieval paint scheme surviving beneath discoloured surface coatings and overpaint.
At the start of the process of protecting fragile paint with facing paper. The altarpiece is made of three boards, probably of limewood; the joint between the second and third boards has opened but the frame holds the panels together.
My priority was to get the altarpiece back to the conservation lab, where it could be removed from its frame so that I could examine the back and stabilise the paint. I held loose paint in place with protective facing paper which I gradually removed as the surface was consolidated over the next five years. To establish the most appropriate materials for conservation, I carried out many trials.
Using high magnification, I examined the painted surface and gradually removed layers of wax and discoloured coatings. As work progressed it became clear that the altarpiece is a complex mixed-media object, which meant that a wide range of techniques were used for treatments. In places the later layers were removed mechanically, using sharp micro-scalpels, whilst elsewhere a variety of solvents and poultices were needed.
Paint analysis has revealed a rich, costly range of colours and fascinating painting techniques. For example, large areas of gold are set beside the crystalline mineral azurite. This blue pigment was bound with glue, resulting in a matt but vibrant colour, seen at its best against burnished gold leaf. Analysis revealed that combinations of linseed oil, animal glue and egg tempera were used to bind the pigments. It also indicated areas where drastic alterations have taken place.
The draperies of the two main figures are now dark, where once they would have been bright. Here silver leaf has darkened or been abraded, leaving the red/brown clay-based undercoat visible. In places an evocative hint of a yellow glaze on Mary’s drapery or a lustrous patch on Gabriel’s is suggestive of a lost brilliance. The brown of Mary’s hair is an early repaint; it was originally gold, but only a tiny trace of this was found under magnification. An exciting find was the discovery of silvered paper dots, applied to decorate the linings of the cloaks.
Uncovering the azurite and discovering the silvered paper dots
Looking at the cross-section of a paper dot, we see azurite clinging to the bottom, then the glued paper over which is a red preparation layer for the silver leaf. The top layer shows the later overpaint and surface wax coating.
After consolidation and cleaning was complete, the process of gap-filling was carried out, where the surface was particularly undermined by beetle damage or where fragile edges needed supporting. Finally the surface was re-touched, using reversible water colours to reduce the impact of the exposed white gesso, lessen surface distractions, and tone out fillings.
It has taken five years, many hours of research, discussions, reading, and MANY hours of hands-on conservation and I hope that now this altarpiece can be appreciated and better understood, as well as recognised as a significant piece in the museum’s collection.
Eddie Sinclair ACR, Freelance Polychromy Conservator
Cullompton Roman Hoard
The surprise discovery of an important Roman burial group, just before Christmas 2009, meant conservators Andrew, Kirstie and Rowena rushed to carry out emergency treatment to stabilize the finds over the Christmas break. The burial group contained a large upturned broken vessel and a group of two further vessels covered by a shale board. Unusually, one of the two covered vessels was intact. The larger broken vessel was treated before Christmas whilst the remaining finds are currently undergoing treatment in the lab.
April 2010 Update
The next phase in the conservation of the Roman hoard is complete. All of the vessels have been excavated revealing some interesting discoveries. The smallest vessel contained very little archaeology, with only small fragments of charcoal. However the large vessel (x-rayed at the airport) was a different matter and can now be identified as an ossuary.
Underneath an initial layer of stones I found LOTS of bone. Most of the bone was fragmentary and hard to identify and showed signs of being burnt. However some of the larger pieces were clearly sections of lower mandible (jaw bone), what appear to be skull fragments and some ribs.
I also found a significant piece of Roman glass, the top piece of an unguent bottle. It shows signs of melting around the rim, and the bulb from the bottom is missing.
Among the bones there was also a tooth which is not human, it is much too large! I also excavated 44 separate iron items, ranging in size from a small ball shaped fragment to some relatively large pieces, one being approximately 7cm long which is rather unusual for a cremation. All of these are extremely encrusted, so I X-rayed them in the RAMM X-ray unit to help with identification. They and they all look suspiciously like nails!
As the layers of bone and iron deposits were removed, each layer had to be documented and photographed. The amount of cremation material found inside meant it took over 48 hours to excavate.
The bone fragments will now be examined an osteoarchaeologist who will be able to give us more information on the human remains, for example the persons age or gender.
The image above shows Kirstie taking the large intact vessel to be x-rayed at the airport. RAMM conservation team is currently working on the group containing the intact vessel and shale board. The shale board is extremely fragile and fragmentary and will be described in a separate ‘Tale’.
The larger of the two vessels was too big for our x-ray machine in the Conservation Lab. So on 10th February, Kirstie took this pot, which is whole and unbroken, to Exeter International Airport, where security staff allowed us to use their state-of-the-art cabin baggage x-ray equipment to scan the vessel and examine its contents.
The x-rays have shown a glimpse of what is inside and this will help Kirstie when she comes to excavate the vessel. The x-ray confirmed the vessel used to contain cremated human remains for burial. Amongst the soil is a mass of dense material thought to be ash from the cremation. Near the bottom of the vessel are several mysterious ‘curved’ shapes. These maybe larger fragments of bone, or possibly metal objects. We won’t know for certain until the vessel has been excavated.
Cullompton Dig site, courtesy of South West Archaeology Ltd.
The vessel has a very narrow neck which means that the excavation will be a delicate operation. All of the material removed from the vessel, including the soil, any fragments of bone and any other objects will be kept for specialists to study. Each layer that is removed will be recorded with drawings and photographs.
A huge thank you to all of the amazing staff at Exeter International Airport!
More news on the excavation of this vessel, the shale board and the second smaller vessel later in February.
The largest broken vessel was first x-rayed at RAMM to investigate whether it contained a cremation or any metal objects. Due to the density of the vessel contents the x-rays showed no interesting features. The vessel was mapped out and labelled on clear ‘Melinex’ film. Then Kirstie and Andrew began excavating the contents.
They carefully documented the removal of the soil in stages called ‘spits’. The spits varied in depth because a new spit was started when they came across something interesting or needed to remove a shard.
When they were not working on the vessel it was kept damp by spraying the surface with a solution of distilled water and Ethanol. This is done to prevent any mould growth and to stop the Devon clay soil from drying out, and becoming very hard. The excavation process was made easier by keeping the soil damp.
When a shard was removed it was numbered, and cleaned and then left to dry out.
Andrew and Kirstie didn’t find any cremation material in the fill, just a couple of stones, and a very small square cut piece of stone possibly a tessera (small piece of mosaic). The vessel is now stable, safe and awaiting reconstruction.
An Ichthyosaur’s Tale
German intern Verena Schoefer is faced with conserving a huge fossil Ichthyosaur…
I knew it was planned to select the biggest Ichthyosaur fossil in the museum collection for the new displays. But when I saw it, the first thing I thought, was “are you kidding?!”
The fossil was broken in five pieces of different sizes and the break edges were covered with a thick layer of old dark glue and old white plaster which had been used to fill missing areas. The surface was not only extremely dirty; it was also almost completely over-painted with a horrible brown and grey paint. You couldn’t see much of the original. It looked dreadful!
I began by removing the old glue from the break edges with a scalpel. Then I cleaned the surface of the fossil with Smoke sponge (a gentle conservation product), but this didn’t make any difference. So I began to remove the dirt with cotton wool swabs and water, which also removed the horrible brown paint from the surface. I found that there was a lot of beautiful fossil surface underneath the over-paint so I’m removing all the paint and the plaster filling and will retouch just the plaster fills. I will also stick the smaller pieces together again, so we will have just two big pieces to mount for the new display. Joining every piece would make it too heavy; all together it weighs 91 kg.
Woodbury Wedding Dress
The redevelopment is improving the gallery environment so at last a range of costume can be displayed. As textile conservator for the project I am able to closely examine and document items that have not really been looked at before.
One such item is this eighteenth century sack back gown consisting of two parts, the open robe and ‘petticoat’. Made from a woven silk fabric (Brocade) with frilled decoration it shows the richness of a typical costume of the upper classes.
Considering its age it is in very good condition. However during conservation previous fold lines and stitch marks were discovered, indicating that the skirt has been considerably altered. Conservation is still in progress, the embroidered cuffs need cleaning.
When the gown goes on display, what an eighteenth century lady would have worn underneath has to be considered. Skirts in this period were worn wide and in order to support the huge quantities of fabric a frame called a ‘pannier’ would have been worn underneath. This will be reproduced in order for the gown to look ‘authentic’.
Anne Amosford, Textile Conservator
A Polar Bear
Interns Vicky and Ashley prepare the polar bear for the new displays.
This polar bear (Ursus maritimus) is part of the diverse natural history collections at RAMM. It was donated by the estate of Charles Peel dating from the early twentieth century. The polar bear was originally displayed as part of a large diorama, in which it was seen to be attacking a seal with the front left paw positioned on top and embedded in the seal. When the display was dismantled the seal was removed resulting in the loss of the attacking paw. Damage from the old display and pest attack, combined with long exposure to sunlight and pollutants from open display, meant that the polar bear had become dirty and needed many repairs.
Starting bottom up
Work began from the bottom up, starting with the recreation of a snowy landscape. It took many hours to carefully cover the front left paw and part of the back left paw which were missing.
A thick layer of dust covered the entire surface of the bear. The cleaning began with the brushing and vacuuming of the hair. This was followed by running Smokesponge (vulcanised rubber sponge) across the hair then swabbing it with a solution of alcohol and water. The surviving paws were covered in old paint and glue which had to be painstakingly removed.
As polar bear hair is unavailable other hairs had to be creatively resourced. A combination of cow and goat hair was used to infill and reconstruct missing areas. The goat hair was kindly donated by the Exeter Hide and Skin Co. Ltd. The front right paw of the polar bear was missing three toes. To reconstruct these, a papier maché base was created and covered with tinted goat hair. Using the other claws, a mould was made in order to cast replacement claws from plaster. The polar bear was also missing his tail which was reconstructed using the same technique as the toes. The new tail is secured in place by wire. Breaks in the ear were re-attached and other cracks that had formed in the painted features on the face were filled in and in-painted.
Splitting at the seams
Shrinkage of the skin had caused three of the seams on the underside of the polar bear to split open exposing the interior fill. These seams were first patched with tissue and then a layer of tinted goat hair was adhered to the tissue to hide the repair.
The polar bear will be redisplayed in the Case Histories Gallery.
Thousands of Shells
47,285 shells and still cleaning!
Where to start…? Approximately two years ago the conservation team began the task of preparing the shell collection for its return to RAMM. This involved condition checking, cleaning and repacking the shells and conserving historic packing materials. This collection area contains specimens of international importance, but until the redevelopment had not been a priority for treatment. In fact, it had not received any conservation attention since it was acquired by the museum.
Some sections of the collection are well documented, others less so – from the patchy documentation, curators estimated that there were approximately 38,000 shells to clean and repack!
We condition checked the shells to assess whether the collections had any mould growth, if the shells had developed Byne’s disease, or if there were signs of pest infestation. All the shells were cleaned and treated with an alcohol solution to kill any mould growth.
In the case of the Linter collection all of the shells were donated to the museum in small black presentation boxes, some of which were in poor condition and needed conservation. In addition to cleaning the shells we also re-adhered box corners, cleaned their glass lids, and then relined them with polyester wadding and spider tissue.
Two years since the project began and with the help of 11 volunteers, nine interns and nine staff we have cleaned 47,285 shells and we are still going strong! There are five more cabinets to complete, as well as approximately 50 more storage boxes, each with an unrecorded number of shells within.
The conservation team would like to say a huge ‘thank you’ to all those who have helped us with the shell collection so far. There are still shells to be cleaned so if you would like to get involved please contact us through the volunteering pages on the website.
RAMM’s shell collection will be moved into More in Store, a new collections study centre in the Queen Street building that will allow the public greater access to our historic collections.
For those of you not familiar with the collection, Gerald is the name affectionately given to our bull giraffe, donated to the museum by Charles Victor Alexander Peel in 1919.
Gerald was one of only two objects not removed to our off site store when the museum closed – the other one being the elephant. Before being lifted into his final position in the gallery, the conservation team took the opportunity to assess his condition and clean and repair those hard to reach areas.
Gerald has spent the last three years tilted nose down in a purpose built crate covered in dust sheets whilst the building work progressed. On 17th of August 2010 he was squeezed out of a (big) window and craned through the roof into his new gallery.
Since he went on display in 1920 Gerald had mostly stayed in one spot, but over the last few months he’s been tilted nose down, had a ride on the back of a lorry, tilted upright again, craned over the museum and tilted back down on his nose again – all of which can put a lot of strain on a very large, 100-year-old taxidermy specimen, not to mention the numerous ‘repairs’ carried out over the years.
Time has taken its toll on Gerald
In his position in the old gallery, Gerald’s head was very close to the roof lights and over the years most of his spots had faded in the sunlight. He has lost most of the hair from the top of his head, the skin had split around the horns and there are lots of areas of hair that had been lost to moths and beetles and rumour has it that his tail is actually from a cow.
Gerald is not all in one piece either. Back in 1901, the skin was originally divided into small manageable pieces that were shipped back from Kenya to the taxidermist Rowland Ward of London. Here a giraffe shaped frame was made onto which the skin was reassembled by stitching the smaller segments back together again.
Some of these joins are easy to see, especially at the top of the legs. Due to shrinkage and movement of the skin, however, the stitching has broken in many areas, opening the joins again, and people have tried many times to fill these holes.
Other old restorations had attempted to make him look more ‘giraffe like’ by painting new spots and applying yellow pigment to the faded head and neck. Replacement hair has been glued to the horns, mane and tail to cover the bald areas and two or three different resins and fillers had been used to fill splits and holes in the skin – especially around the top of the head and horns and between the legs.
The week before he was put upright, the conservation team worked to clean and vacuum off building dust. We also looked at the painted spots and yellow colouring to the head – most of which do not seem to be painted over any original markings, so these were reduced to try and bring back Gerald’s original markings and hair colour.
On the left is Gerald before cleaning, looking very yellow. On the right is Gerald after cleaning, with a more natural colour and more of the original skin revealed – especially around the mouth area.
He was lifted upright for the last time just before Easter, and put in the final position in the new gallery. But the conservators’ work is not done yet – see next time to see what happens to taxidermy bases over the years, the interesting things you find inside and if the tail is really from a cow…
RAMM’s Queen Street entrance mosaic
During the redevelopment the mosaic above the Queen Street entrance was covered with layers of spider tissue and calico to help protect it from vibration damage that could have occurred because of building work and demolitions that took place directly above it.
This protective cover was removed carefully just before the re-opening. Two conservators spent 3 days removing the protective covering, and cleaning the mosaic.
As the mosaic began to re-appear it was revealed that no damage had been sustained throughout the building works. For the two conservators who worked on the mosaic and many of the new museum staff this was a fantastic opportunity to see a part of the museums history that they had not seen before.
The mosaic now once again shines brightly above the Queen Street entrance.
Improving access to the Greek and Cypriot collections
RAMM’s Greek and Cypriot archaeology collection contains around 500 objects from Neolithic stone tools to Roman glass. Funding from the AG Leventis Foundation is enabling staff and volunteers to conserve, photograph and research these collections. RAMM’s Conservation team are repacking the collections in store, and conserving objects to make them safe to handle and suitable for display in the future.
More than 20 objects from this collection have now received individual conservation treatment, varying from minor treatments like removing mould, to more extensive treatment like full reconstructions. Once objects have been conserved they will be re-located into RAMM’s ‘More in Store’, in the heart of the museum.
Examples of objects that have been conserved include:
- Glass drinking vessel. Originally in 5 pieces, two of which were delaminating sections. 90% complete, with iridescent weathering.
- Glass vessel originally in 20 pieces. Object has localised area of iridescence and insoluble salt deposits. Larger shards have running cracks.
- Ceramic bowl originally in 11 pieces, 95% complete. Thin layer of surface deposits (possible archaeological deposits). Clean break edges.
- Rider and horse. Originally in 6 pieces, the figurine is creamware with red strips. (A similar figure can be seen in the Ancient Worlds Gallery)
- Ceramic vessel in 7 pieces. The vessel has salt deposits and structural cracks.
- 5 chicken figurines and 3 ceramic sherds. Repacked into a more secure environment, ideal for handling purposes.