Conservation of Theban Tomb Paintings, Luxor, Egypt: The Tomb Chapel of Sennefer, a Case Study

 

For our first meeting of 2018, OCG was delighted to welcome Bianca Madden, an independent art conservator who specialises in wall paintings, sculpture and polychrome or gilded surfaces, to talk about her work on the fifteenth century BCE Theban tombs in Egypt. Bianca took us on a spectacular virtual tour of the tomb chapel of Sennefer, which is very typical of many Theban tombs in regard to its condition and state of preservation. Her presentation showed the group not only the method of construction and the nature of the painting media but also the conservation approach that she and an international team of conservators took to reveal details that had been obscured for centuries, largely due to damage caused by natural degradation over time as well as previous human activity.

The conservation project at Sennefer began in 2001 as a joint enterprise between Brussels and Liège Universities as a part of their research and study project at Sennefer which started in 1999. Unlike the burial chamber of Sennefer, which has long been open to the public, the tomb chapel is unlikely to be opened for public viewing due to its extensive damage and fragmentary state. The approach to the conservation of the tomb was as a monument which would primarily be used for study and research rather than tourism. This intended research function guided the conservation approach, with a clear emphasis on minimal intervention and maintenance of the integrity of the tombs rather than restoration.

Damage to the tomb came from several sources, some historical and some more recent. The tomb, in common with many of the Theban tombs, had a history of human occupation, and until 2008 one hall was still being used for storage. This human activity had lead to heavy soot, mud and mould deposits on the interior walls and ceilings in particular. Attempts by early Egyptologists to reveal the wall paintings beneath the dirt layer by water washing had caused mobilisation of the water soluble tempera-based media, with irreversible losses to both the figures and the backgrounds. Insect pests had also been an issue related to the human occupation and the stabling of animals within the tomb, and masonry bee nests were burrowed into the walls. However, where losses had occurred to the plaster, the damage had revealed fascinating aspects of the construction of the tombs and the preparation of the walls for painting. The stratigraphy of the plaster layers was revealed over the hewn limestone rock, and in some areas the clear evidence of the hands that had applied the initial rough plaster layer several millennia previously was still visible.

Image with kind permission of Hugues Tavier, University of Liège

The conservation was undertaken in two phases: to stabilise the construction of the tomb rooms and to clean and stabilise the wall paintings themselves. The nature of the rock strata on the site had made the detachment of the plaster more liable, so stabilising the ceilings in particular was a primary concern. A low humidity, lime-based mortar, PLM-A, was used to readhere loose areas of plasterwork. The introduction of this new material was restricted only to where it was strictly necessary with edge repairs being used rather than infills wherever possible to maintain the constructional evidence.

Phase two was the cleaning and stabilisation of the media. Bianca began by showing how the paintings were built up in layers, with some incredibly vital images of underpainting and the use of a grid system for figures to ensure evenness and regularity of the form.

Image with kind permission of Hugues Tavier, University of Liège

It was a revelation to see that not all the paintings were two dimensional but had texture and relief through applied plasterwork features to areas such as head dresses, the effect of which was enhanced further with localised applications of varnish.

Such features contributed to making the cleaning and stabilising of the media a painstaking process. There were three approaches to removing the damaging and acidic soot and the heavy mud deposits. Brushes combined with blown air were used to remove loose deposits, followed by surface cleaning using a wishab sponge, a type of latex cleaning product that absorbs dirt but crumbles as it is moved over a surface, limiting the abrasive capacity and reducing the risk of residues. Heavy mud deposits were scraped away under magnification using a scalpel, revealing in many cases very well preserved paintings below. Spot tests showed that a very minimal and localised application of moisture would remove the remaining dirt deposits. A poultice of PLM-A, applied through Japanese tissue, was used with startlingly effective results to wick away residual dirt, as the images below show. The alkalinity of the lime mortar also had the effect of deacidifying the soot deposits, resulting in a neutral surface pH. Where necessary, pigments were consolidated with carboxymethyl cellulose solution.

 

Ceiling before cleaning, and after

The many and varied questions at the end of the presentation showed the level of engagement and interest of the group, and we are grateful to Bianca for sharing her fascinating work with us. It felt as though we were getting a very privileged glimpse into a highly significant site and to have Bianca’s expert guidance and knowledge to interpret and explain the magnificent images was both hugely enjoyable and invaluable to increasing our understanding of this specialised conservation project.

Our sincere thanks go to Bianca for presenting to the group, and to the Oxford Conservation Consortium and the Chantry Library for kindly hosting the event.

 

Tomb images kindly provided by Bianca Madden and Hugues Tavier on behalf of the University of Liège and the Archaeological Mission to the Theban Necropolis – Université libre de Bruxelles, and the image of the group kindly provided by Nikki Tomkins on behalf of the Oxford Conservation Consortium.

Raw Hide: a librarian’s journey into the nature of the beasts

This post has been written by Julie Blyth, Assistant Librarian at Corpus Christi College Oxford and our Committee of College Librarians representative on OCG, following the course on leather identification given for the Oxford librarians and cataloguers in March.

Last month 15 of Oxford’s early printed book cataloguers met for a training course on leather species identification.  The course was run by Yvette Fletcher of the Leather Conservation Centre in Northampton, ably assisted by book conservator Rosie.  Yvette started with a quick gallop through historical leather technology, complete with wonderful illustrations, many of them from historic sources.  This was followed by an overview of the causes and outcomes of deterioration, and then it was on to looking in detail at follicle patterns.  We were all nodding wisely until presented with our own little sample packs, and then the hard work of practical identification began!  Huddled over our smart-phones with microscope attachments, we squinted and muttered until giving in and asking for help.  Slowly, by a process of elimination, we are able to discern the differences between sheep and goat, calf and hair-sheep.  Light relief was provided by the piles of leather samples from all over the world that Yvette had brought with her, from the softest top-quality kid to the creepiest of chicken feet.

It was a fascinating and truly worthwhile day, and we look forward to putting our freshly-honed skills into practice.

 

New online: Welsh manuscripts

Several important Welsh medieval manuscripts belong to Jesus College, most famously the Red Book of Hergest. These manuscripts were photographed twenty years ago for the pioneering digitisation pro…

Source: New online: Welsh manuscripts

From rocks to riches: object analysis using X-ray Fluorescence (XRF)

OCG Occasional Series on Analytical Techniques 1, presented by Dr Kelly Domoney, Ashmolean Museum

OCG members and friends pack the Headley Lecture Theatre at the Ashmolean Museum

There was an impressive turn-out of members and friends for this, the first in our Occasional Series on analytical techniques that have useful applications in conservation. The Headley Lecture Theatre at the Ashmolean Museum was packed with conservators, librarians and archivists keen to find out more about this key non-destructive identification tool which has broad scope across many conservation disciplines for dating, characterisation, checking authenticity and potential previous restoration of materials and objects.

Dr Kelly Domoney using the handheld XRF spectrometer

Dr Kelly Domoney, Preventive Conservator at the Ashmolean Museum and Lecturer in Archaeological and Conservation Science at Cranfield University, delivered a very well structured and refreshingly clear presentation on the principles of the technique and the range of equipment available. XRF analysis works by measuring secondary, or fluorescent, x-rays from a study sample that has been bombarded with primary x-ray energy.

Each individual element is characterised by the energies of the secondary fluorescence, and from this information can be distinguished and identified. The range of elements that can be identified is dependent on the equipment used, and this session focused on the portable, handheld type of spectrometer originally used in the mining and scrap metal industries for the separation of metals and geological ores and is now frequently found in the museum conservator’s toolkit. Although a very wide range of elements can be identified using this equipment it is more limited than static lab based spectrometers.

An example of the analytical capacity of the technique

However, it was clear that handheld XRF is very useful to provide almost instant identification of metals and metallic elements in composite museum, library and archive objects. It was interesting to appreciate the complexities of the process by which x-rays can penetrate the surface of a given object and the depth of analysis depending on its composition. More dense materials, such as metals, have a shallower field of analysis than objects composed of, for example, wood or paper. This has clear implications not only for the accurate interpretation of the graphed data but also for the safe use of the technology.

There followed a practical session using the Ashmolean Museum’s spectrometer, which really engaged the group and gave participants a very clear understanding of both how the equipment worked and the resulting data can be interpreted. Kelly distributed several samples including a fork, a seal matrix and fragments of both majolica ware and painted Meissen porcelain, and asked participants to hazard a guess as to their composition before analysis.

I need an audience member for my next trick: positioning the seal matrix for analysis

For each sample Kelly demonstrated the capacity of the various standard menus for the machine and the flexibility of the data analysis programme, as well as interpreting the graphed data for each object. Using the spectrometer’s camera setting it was clear that to achieve accurate results careful placing of the object for analysis was essential, particularly in complex composite object, such as the painted porcelain.

Interrogating the data using the spectrometer’s software

Each XRF shot can analyse a surface area of approximately 0.5cm square and making sure the correct part of the object was analysed was a delicate and time consuming process. The process itself was simple, but the interpretation of the data required skillful judgment, as other elements within the sample, in particular those with layered structures such as gilded metals, can be detected by the equipment and affect the results, and so identification.

OCG are very grateful to both Kelly and the conservation department at the Ashmolean for enabling this lecture to take place and for providing such an impressive launch event for our Analytical Techniques Occasional Series. It fulfilled the brief for the series very well, by demystifying and demonstrating the method, means and scope of XRF in a way that was accessible to all participants. The bar has been set, and we await future lectures in the series with keen anticipation.

‘More than the value of a pig’: OCG visit to the Pitt River Museum’s new Cook Voyages collection case and talk by Jeremy Uden, Deputy Head of Conservation, 6 April 2016

Our first view of the case

The first sight of the Tahitian mourner’s costume, which holds a prominent place in the new Cook Voyages display at the Pitt Rivers Museum, was sufficient reward for the postponement of lunch for the OCG members who attended this event. Crowding to see the contents of the new case in the first floor gallery space, members were impressed by the skilful layering and the pleasing density of the objects on display. We were to discover that key objects, in particular the mourner’s costume and the war head-dress of Potatatau, dictated the case’s superlative dimensions in width and height respectively. It was clear from the start that the collection told the story of the people who Cook interacted with on his voyages, not of the man himself or the collectors who accompanied him.

OCG members looking at the case display

In his presentation, Jeremy highlighted aspects of the history of this collection, one of the most important material records of pre-contact Pacific cultures. Based on two very well documented collections, and in particular the Forster collection which was advantageously listed in the 1776 Catalogue of Curiosities, 200 objects have survived in the museum’s collection today.

There followed a detailed description of the chief mourner’s costume: a magnificent bringing together of a wide range of materials including pearl shells, the scant tail feathers of rare birds, human hair and bark cloth. These ceremonial robes had social, political, spiritual and genealogical importance, and represented a significant investment for the communities that produced them, not least in financial terms. The pearl shells which form the breastplate were items of extremely high value and in the context of high-status decorative objects were known to be worth more than a pig to the communities who prized them.

The costume after remounting; it’s an impressive object

The conservation and remounting of the mourner’s costume was made necessary by the existing mount, which not only truncated the costume but was actively damaging it. The lengthy conservation process was detailed by Jeremy, including the use of undyed Japanese tissue to support damaged areas of the bark cloth so that new repairs would be easily identified in the future. The sleuthing tendency in all conservators was gratified in this treatment, as a separate unidentified piece of bark cloth in the collection was found to be a missing part of the cape and subsequently reintroduced, filling in one of the missing jigsaw pieces that make up this complex object. Working with Victoria and Albert Museum conservator Rachel Lee, Jeremy showed the group a short stop-motion film of the remounting of the mourner’s costume, which emphasised its multi-layered, composite makeup extremely well. A link to the film can be found at the end of the post; it is well worth viewing. The over-riding sense when watching the film was one of respect for the level of craftsmanship that had been employed in the costume’s construction, and for the startling effect it would have achieved when it was ceremonially worn.

The scale of the new case is clear from this image

Jeremy then described the construction of the case, and its attendant frustrations. The fact that it had to be craned in sections into the museum via a first floor window will give an idea of the scale. The use of an aluminium frame meant that the case was significantly lighter, by around a tonne, than it would have been if a traditional steel frame had been used. The main issues once constructed were the need to change the composition of the display panels from Forex (closed cell PVC board) to cellulose lacquer-coated zero formaldehyde MDF due to Forex failing Oddy testing, and the subsequent need to allow the case panel coatings to off-gas. 18 months from its installation the case was ready to be filled.

The case design followed the journey of Cook through the Pacific, a courteous nod to the previous Cook Voyage case curators, by highlighting the material objects of the various cultures he encountered along the way by geographical area. Out of the 200 objects in the collection an impressive 196 are on display in the new case. This density which contributes so much to the effectiveness of the display meant that some very intelligent mounting was required, with items being partially displayed from behind information panels and the use of rolls to display bolts of bark cloth allowing them to lie in a natural, uncontrived way. The overall effect was almost one of looking into the imaginary store-rooms of these communities, and seeing both the wealth and richness of ceremonial objects complemented by the everyday tools and objects, such as the Tongan fishing net, that allowed people to live and work.

Our sincere thanks to Jeremy Uden, Heather Richardson and all in the conservation team at the Pitt Rivers Museum for their generous hosting of this event. Images by kind permission of the Pitt Rivers Museum, Oxford.

http://conserving-curiosities.blogspot.co.uk/

 

Enwrought with gold and silver light: the OCG Conservation Forum 2015

The intertwined warp and weft of OCG’s membership was very clear in this year’s Forum, held on 6 October 2015 in the Education Centre at the Ashmolean Museum, with visually impressive presentations on a diverse range of textile-related conservation projects. An over-arching theme was the power of conservation to reveal that which was previously hidden: textile objects tucked into expansive archive collections, tiny carpet fibres in an archive carefully compiled over a lifetime of analysis and research, hidden clues to binders’ working methods in textile bindings from the library of Henry VIII and vibrant colour schemes, and the use of surprising materials, rediscovered in seventeenth century embroideries. There was an emphasis on collaboration too, with the mutual benefits of inter-disciplinary working to complete conservation projects being demonstrated very well by all of our five speakers.

A full write up will appear in the November 2015 edition of Icon News, but until then I have attached our Forum poster for you to see the speakers, their subjects and a small embroidered jewel in the textile treasure trove we enjoyed.

OCG Grand Day Out: Douai Abbey and the Wintour vestments

  

It was a small and select group that headed out into the wilds of West Berkshire on Friday 27 September for the first ever OCG Away Day. Destination: Douai Abbey, a Benedictine monastic community founded in 1615 in Paris, but resettled in Woolhampton, near Newbury, in 1903. We were made very welcome by archivist Alison Day, who was our personal guide to the Abbey’s exhibition of magnificent early modern vestments, mostly dating from the seventeenth century. OCG were very fortunate, as we were attending on the last official day of the exhibition before it transferred to Auckland Castle, Co. Durham, where my sources tell me it will be joined by Oxford’s most famous Guy Fawkes object, his lantern, on loan from the Ashmolean Museum.

This remarkably preserved set of vestments were the work of Helen Wintour, daughter of Robert Wintour who was executed for his part in the Gunpowder Plot of 1605. On Helen’s death in 1670, the vestments were split between the English Jesuits and Helen’s aunt, Lady Mary Wintour. Within the twists and turns of history, the Jesuit part of the collection came to be owned by Stonyhurst College in Lancashire and those belonging to Mary Wintour came to Douai Abbey, having passed through the ownership of a number of Catholic recusant families on the way. Importantly, the Douai Abbey exhibition is the first time the collection has been complete since 1671. As well as the Wintour vestments, several other remarkable items were available to provide historical context to the collection, with portraiture, silverware and objects related to the celebration of Mass all on display.

Alison was an accomplished guide, with extensive knowledge and understanding of the techniques used in the textiles’ construction. The work was of an incredibly high standard, and it is probable that Helen Wintour had the guidance of professional broiderers, even if the work itself was her own. A recurring theme was the symbolic and beautifully naturalistic depictions of plants and flowers, including the use of flowers recently discovered and brought to Europe, perhaps indicating Helen’s other interests and certainly her status. Alison detailed the stitching methods used, and in particular how the three dimensional structure of many of the applied decorative panels was achieved by padding out with suede before embroidering. This created a remarkably rich and luxurious effect, which in candlelight must have been breathtaking. There was humour too: embroidered sheep nosily peeping through the stable windows in Bethlehem and most charmingly the devil dressed as a woman, complete with embroidered lipstick, attempting – but unsurprisingly failing – to lure Jesus in the wilderness. The clawed feet, hands and the horns kind of gave the game away, no matter how much early-modern Prada he wears.

There clearly had been some conservation work undertaken on some of the vestments. This was done at various times, some with a great deal of skill and care, in other cases with a good deal of enthusiasm and goodwill.

The day was rounded off with a very welcome slice of cake and a cup of tea at the Abbey’s very fortunately timed Macmillan charity afternoon tea, so OCG members hit the roads of rural Berkshire refreshed in both body and mind.

My thanks to Alison, the Right. Rev. Geoffrey Scott and all members of the Douai community for a visually dazzling and memorable visit. All photos appear here with the kind permission of Douai Abbey, and my apologies for the reflection on some of them.