Item Open AccessSubliming Surfaces: volatile binding media in heritage conservation(University of Cambridge Museums, 2018) Rozeik, Christina; Rowe, Sophie; Tissier, Frédérique-Sophie; Skinner, Lucy; Kariye, Hiroko; Piotrowski, Kelli; Soppa, Karolina; VonStein Murray, Courtney; Stein, Renée; Taylor, Jeannette; Peters, Nicole; Shugar, Aaron; Ploeger, Rebecca; Ravines, Patrick; Adlem, Martin; Hackett, Joanne; White, Grace; Kasiulytė, Rūta; Garšvienė, Sandra; Peters, Renata F; Ohara Anderson, Eri; Langdon, Katherine; Dittus, Alexander; Bisbing, Richard E; Norton, Ruth; Davidson, Amy; Perkins Arenstein, Rachael; Brown, Gregory; Groenke, Joseph R; Brown, Matthew; Mas-Barberà, Xavier; Kröner, Stephan; Orozco-Messana, Javier; Grafiá-Sales, JV; Raffler, Susanne; Bichlmair, Stefan; Kilian, Ralf; Krus, Martin; Hensick, Teri; Sigel, Anthony; Lie, Henry; Khandekar, Narayan; Smith, Kate; Bewer, Francesca; Chang, Angela; Orsini, Louise; Mysak, Erin; Bonnat, Mélodie; Miller, Eric; Harrison, Lynne; Howard, Helen; Rozeik, ChristinaThis book brings together 22 papers and posters that were presented at the conference ‘Subliming Surfaces: Volatile Binding Media in Heritage Conservation’ in Cambridge, April 2015. Item Open AccessReversible internal wall insulation for historic buildings using cyclododecane as a protective layer(University of Cambridge Museums, 2019-09-01) Bichlmair, Stefan; Krus, Martin; Kilian, Ralf; Rozeik, ChristinaTraditional wall-mounted insulation systems can be difficult to mount in historic buildings without damage to original interior surfaces and plasters. This can lead to restrictions in retrofitting energy saving measures like internal wall insulation. This poster describes the development of a new reversible mounting system using cyclododecane (CDD), a volatile binding medium. CDD allows the application of different internal wall insulation systems without damage to the underlying wall. A preliminary study using an adhesive mat as a separating layer proved promising, but allowed mould growth because of airflow. To avoid this problem, a fully-reversible system was designed, using CDD in combination with a newly-developed plaster. A case study in the 18th-century Alte Schäfflerei building, now the Fraunhofer Centre for Conservation and Energy Performance of Historic Buildings, tested the suitability of this system in a historic building. Ten different internal wall insulation systems were tested on prepared test fields containing matrices painted with original colour binder systems. Each test field was about 10 square metres in size and included a window with window seals and reveals. Measurements of temperature and RH, and metrical and visual comparative assessments were made on these test fields in order to find out the long-term effect of the insulation systems on the underlying historic lime plaster. This research demonstrates that it is possible to design a reversible interior insulation system using CDD as a protective layer for original surfaces on historic buildings. Item Published version Open AccessCyclododecane for mounting of surface sensors for monitoring of historic buildings(University of Cambridge Museums, 2019-09-01) Raffler, Susanne; Bichlmair, Stefan; Ralf, Kilian; Rozeik, ChristinaIn heritage buildings, monitoring of the hygrothermal behaviour of building components and of the indoor climate is often necessary for conservation purposes. In many cases, measurement on sensitive building surfaces is required, which necessitates direct contact between the sensor and the surface over the entire measurement period. Commonly-used mounting systems cannot be removed without damage to historic surfaces. This paper describes a new system for mounting sensors on valuable historic surfaces, developed in cooperation with conservators and building physicists. Various materials and methods were tested in the laboratory and in situ for applications indoors and outdoors. Cyclododecane (CDD) was used as a protection layer to protect original surfaces, and also as a contact layer for accurate measurement. Since CDD is a volatile binding medium, sublimation must be hindered until the measurement period has ended by covering with a diffusion-tight material. CDD can be a solvent for some materials, so conservators should ensure that no reaction occurs between the covering layers, the CDD and the historic surface. The development of the covering layers and their application methods is presented in this paper. The effect of this new reversible mounting system on measurement accuracy is also examined and discussed. The system has been applied and monitored several times in museums and castles. The historic surfaces were assessed afterwards for damage or residues. The system is almost completely reversible and does not affect measurement accuracy significantly. Item Open AccessRuled out: the use of cyclododecane as a temporary facing during the removal of a canvas lining from a fresco of a kneeling flagellant and Saints Michael and Stephen by Spinello Aretino(University of Cambridge Museums, 2019-08-01) Miller, Eric; Harrison, Lynne; Howard, Helen; Rozeik, ChristinaThree fragments of an early fifteenth-century Italian fresco, The Fall of Lucifer by Spinello Aretino, were presented to the National Gallery, London by Sir Henry Layard in 1886. They were detached from the wall above the high altar of Compagnia di Sant'Angelo, or S. Michele Arcangelo, in Arezzo by the strappo technique and lined onto canvas. Movement and shrinkage of the animal glue lining had caused buckling of the fresco, a long-term problem that led to losses from the fragments. A treatment programme to transfer the fragments to solid supports was proposed, using a facing of Japanese tissue paper applied with Klucel G and consolidation with cyclododecane (CDD) to strengthen the structure while the canvas was removed. However, the mordant securing the tin-leaf decoration was found to contain oil and sandarac resin, and there was uncertainty about the effect of prolonged immersion in PET (used to remove the CDD after treatment) on the mordant. The animal glue that holds much of the paint layer together, and some of the pigment binders, were also soluble in water, making the use of Klucel G inadvisable. The Klucel G facing was integral to the treatment plan, so the plan to remove the canvas was abandoned, also ruling out the use of CDD. As a result, the treatment proposal was reassessed in favour of retaining the canvas layer. Item Open AccessCyclododecane as temporary protection on distemper wall paintings prior to plaster consolidation: the temple restoration project in Sikkim(University of Cambridge Museums, 2019-06-01) Bonnat, Mélodie; Rozeik, ChristinaCyclododecane (CDD) is a volatile product that was successfully used by wall painting conservators during conservation of wall paintings in the Hee Gyathang and Singhik temples in 2014 and 2015. In this region, restoration projects have been taking place since the Buddhist-built heritage suffered from a severe earthquake in September 2011. Developing an adequate and ethical restoration method adapted to the artefact’s characteristics is a challenge, considering the unique context of the project. Most Sikkimese temples built after the seventeenth century are decorated with religious murals, traditionally painted with animal glue mixed with pigments and applied on earthen plasters. The hydrophilic characteristics of these materials set strict parameters for the conservator, who must limit water and abrasion throughout the restoration process. The presence of a varnish may allow the use of Japanese paper glued with methyl cellulose as a protection, but this is impossible on unvarnished surfaces. Due to strong vibrations from earthquakes, plasters are commonly detached from the wall so consolidation by grout injection is necessary. It is crucial to avoid grout leaks at the surface of the original paintings, since stains from grout on matte paint are almost impossible to clean. In order to protect the paintings, CDD was tested. It was prepared in saturated solution with cyclohexane, slightly heated in a convenient electrical baby milk bottle heater and applied with a smooth brush on the paintings. The CDD layer was very thin and almost transparent but thick enough to repel grout leaks and protect the paint layer during the grout injection. After three days, the CDD was totally sublimed, having protected the decorated surface from all residues and successfully preserved the matte and bright appearance of the paint layer. The temporary protection of water soluble murals with volatile CDD was a good alternative to Japanese paper and methyl cellulose. The product seemed to behave acceptably on glue-based matte painting in a relatively humid and temperate climate and could be used for future conservation projects of unvarnished matte murals. Item Open AccessProtection and relocation of frescoes during construction at the Harvard Art Museums(University of Cambridge Museums, 2019-06-01) Hensick, Teri; Sigel, Anthony; Lie, Henry; Khandekar, Narayan; Smith, Kate; Bewer, Francesca; Chang, Angela; Orsini, Louise; Mysak, Erin; Rozeik, ChristinaThree frescoes painted in the 1930’s by social realist artists Lewis Rubenstein and Rico Lebrun needed to be consolidated, protected and moved during major renovations to the Harvard Art Museums between 2009 2 and 2014. During construction, the frescoes, measuring a total of 22.3 m , would be subject to relocation, shock and vibration, climate extremes and structural intervention. Conservators devised a cyclododecane (CDD) facing as part of a multi-layered system of protection designed to remain in place for several years. Two of the fresco walls, weighing many tons, were cut from the existing masonry and moved by crane, while one of the frescos remained in situ on the inside of an exterior wall, protected from the elements by a purpose-built housing. The project allowed comparison of two techniques for applying molten CDD on a large scale: by spraying through a gun designed for hot-melt glue, and by painting with hog hair brushes. Ultimately, brushes proved quicker and easier to use. Testing at various temperatures revealed new information about CDD’s behaviour. Though it reportedly melts at 60–71°C, it was significantly more fluid and easier to apply during testing in the 80–85°C range. Heating the CDD above 85°C using a hot glue gun resulted in samples that became tacky shortly after application. FTIR analysis revealed changes in the aliphatic stretching and bending regions of CDD in these samples. The analysis suggests that CDD can be safely heated to 80°C without causing molecular changes. The CDD facing successfully preserved the fragile fresco surfaces, remaining intact under a Marvelseal barrier film for over three years. Upon removal of this protective seal the CDD completely sublimated with the help of fans, localised heating and ventilation. Item Open AccessThe use of cyclododecane as a separating layer during the moulding of porous stones(University of Cambridge Museums, 2019-06-01) Mas-Barberà, Xavier; Kröner, Stephan; Orozco-Messana, Javier; Grafiá-Sales, JV; Rozeik, ChristinaThe physicochemical properties of outdoor moveable artworks are modified by degradative environmental agents and biodeterioration. In many cases, the most effective action or intervention is to replace an artwork with a copy, moving the original into a museum or another more protected place. In general, this process entails moulding of the original and its reproduction using restoration mortars. This study evaluates the possibility of using cyclododecane (CDD) as a temporary barrier film during the moulding of extremely porous stone sculptures and ornaments. For this, samples of a travertine (calcium carbonate rock) called Tosca Rocafort were prepared. These travertines, exceptionally porous with numerous cavities, can be percolated in an irreversible way by moulding materials during the process of making a copy. By using a CDD barrier layer, the pores are sealed without losing the texture of stone substrate, and at the same time the silicone moulding material is prevented from penetrating the porous stone. To solve the problem of an affinity between the CDD and the silicone (both of which are non polar materials), several polar substances (4% agar-agar in water and pure latex) were tested as an intermediate insulation layer. This proposed method, based on a system of layers with different polarities, allowed us to isolate and protect the porous stone from the silicone elastomer, which is the cause of irreversible stains on stone substrates during mould-making. As an isolation layer, agar-agar proved unsatisfactory as it formed heterogeneous layers with low physical resistance, resulting in residues of moulding materials on the stone suface. In contrast, latex created homogenous layers while transmitting all details of the surface of the original work – and without leaving residues. The presented multi-layer system for moulding of porous materials has a number of advantages that make it appropriate for conservation and restoration work: good film-forming properties, very low toxicity, and ready reversibility (due to the ability of CDD to sublimate). The CDD film remains in place for long enough to allow the silicone moulding material to become vulcanised. However, it is easily removed through sublimation, which means that no intervention (possibly damaging to the surface of the stone) is necessary to remove the barrier layer. We conclude that CDD is a suitable temporary barrier material on porous stones, creating a homogeneous, impervious and inert film. Item Open AccessSeveral case studies using CDD in paper and textile conservation at the Lithuanian Art Museum’s Pranas Gudynas Restoration Centre(University of Cambridge Museums, 2019-06-01) Kasiulytė, Rūta; Garšvienė, Sandra; Rozeik, ChristinaThe Pranas Gudynas Restoration Centre (PGRC) is a branch of the Lithuanian Art Museum. The PGRC is primarily responsible for the long-term preservation of the Lithuanian Art Museum's collections and also assists in the preservation, conservation and technological study of collections from other Lithuanian museums, churches or institutions. The Centre is the main training base for restorers of portable cultural heritage in Lithuania. We started to use CDD around 2003, when our chemists offered this material for applying in specific conservation situations. CDD is currently used here in paper and textile conservation for fixing water-sensitive materials and as protection against aqueous solutions. This paper describes its use on four objects: two watercolour works on paper, a wooden chest upholstered with silk and metal thread embroidery, and an oil painting on silk. Item Open AccessCyclododecane and fossil vertebrates: some applications for matrix removal, moulding and shipping(University of Cambridge Museums, 2019-03-01) Davidson, Amy; Perkins Arenstein, Rachael; Brown, Gregory; Groenke, Joseph R; Brown, Matthew; Rozeik, ChristinaOver the past decade, cyclododecane (CDD) has been increasingly adopted by vertebrate fossil preparators as a more effective and advantageous material for several standard treatments and for new applications borrowed from art and artefact conservation. Many techniques in palaeontology utilise CDD's special properties, including its use as a temporary embedding and support material to protect fragile specimens during removal of rock matrix; as a barrier layer during consolidation; as a temporary consolidant; as a temporary filler during airscribe preparation; as acid-resistant protection for fossil bone during dissolution of the limestone matrix; as a gap-filler, sealant and separator during silicone rubber moulding; and as a protective coating for specimens that are otherwise too delicate to ship. In several of these techniques, CDD replaces materials traditionally used in preparation - such as polyethylene glycol (PEG), microcrystalline wax or oil-based clay - that must subsequently be laboriously melted, dissolved or mechanically removed. CDD is not used in some fossil preparation laboratories due to health and safety concerns. It is hoped that continued exchange of information with art and artefact conservators will promote safe handling practices, encourage experimentation and spark new ideas. Item Open AccessResidues from cyclododecane consolidation following desalination(University of Cambridge Museums, 2019-03-01) Dittus, Alexander; Bisbing, Richard E; Norton, Ruth; Rozeik, Christina1500 Central and South American archaeological ceramics in the Field Museum of Natural History, Chicago, required desalination treatment. Cyclododecane (CDD) was investigated as a temporary consolidant for extremely friable ceramics during desalination, leading to an investigation of post-sublimation residue. Watch glasses, new unglazed terracotta saucers, and thick potsherds from the archaeological collection were treated and desalinated. No residues were detected after sublimation on watch glasses, the saucers, and archaeological potsherds that did not undergo desalination. Residues were found on all archaeological potsherds that were desalinated. Microscopical study and infrared spectroscopy (ATR-FTIR) indicated the residue to be primarily of biological origin. Its presence could result from the growth within the CDD of bacteria, mould and yeast present in the archaeological ceramic. There was no evidence of CDD remaining in the residue. Residues on desalinated potsherds consolidated with molten CDD were thin, lightly cohesive sheets. The residue could be lifted off with electrostatically charged nylon brush or polyester film. Residues formed in the CDD applied as a solution were less cohesive and could only be removed by brushing. In most cases, some ceramic particles were lost. It was concluded that temporary consolidation with CDD was not useful in desalination treatments. Item Open AccessArchaeological block-lifting with volatile binding media: exploring alternatives to cyclododecane(University of Cambridge Museums, 2019-03-01) Langdon, Katherine; Skinner, Lucy; Shugar, Aaron; Rozeik, ChristinaCyclododecane (CDD) is the only volatile solid currently in common use in archaeology, usually as a consolidant in the practice of block-lifting. CDD is considered by many to be an advantageous consolidant in block-lifting due to the fact that it can be removed from the block through sublimation, whereas traditional adhesive consolidants must be removed (and then only partially) through the use of solvents and mechanical action, which can be hard on the artefacts. CDD’s main drawback is its sublimation rate, which is slow enough that subsequent treatment of heavily coated objects cannot always be completed within a suitable time frame. This research compares CDD with a range of alternative volatile binding media to determine their relative usefulness for block-lifting. Camphene was determined to be unsuitable for archaeological block-lifting due to its lack of rigidity, excessively fast sublimation rate and typical impurity. Menthol was found to have the desired properties but was susceptible to melting in a warm climate, as observed in a field test. Its melting temperature may be ideal in colder conditions. Mixtures of CDD and menthol with a low menthol content were found to have the desired properties but require further testing. Item Open AccessJuggling fire without getting burned: working with cyclododecane in Olduvai Gorge(University of Cambridge Museums, 2019-03-01) Peters, Renata F; Ohara Anderson, Eri; Rozeik, ChristinaFew examples in the literature offer approaches to improve skills or solve the problems that will inevitably arise while working with the often limited resources available in archaeological excavations. Clearly, working in the field is very different from working in the controlled environment of a laboratory. Even very simple things may be difficult to achieve. This poster explores -- in a light-hearted but fully grounded way -- how conservators overcame apparently mundane challenges when trying to use cyclododecane during the 2014 excavation season in Olduvai Gorge, an important Palaeolithic site in Tanzania, where material resources were limited. We demonstrate how much preparation and improvisation are needed to make things work properly and safely. Item Open AccessThe use of cyclododecane as an adhesive for temporary facings in paper conservation(University of Cambridge Museums, 2019-03-01) White, Grace; Rozeik, ChristinaIn recent years, cyclododecane (CDD) has been introduced into the book and paper conservation field as a temporary consolidant for flaking media and as a temporary fixative for water-sensitive media by the formation of a physical barrier against moisture. CDD is particularly suited to these two applications because of its insolubility in water and its ability to sublime without requiring the use of solvents for removal, leaving no residue on the object. This paper will explore a third possible use of CDD borrowed from the fields of archaeology and objects conservation: as an adhesive in the preparation of temporary facings. Various application techniques will be presented and compared. The effectiveness of the treatment will be addressed with a case study of two 18th-century ornithological gouache paintings on thin, brittle, torn paper fully adhered to acidic backing boards. Because of numerous risk factors involved, particularly during removal of the backing, the objects required the simultaneous consolidation of flaking pigment, the fixing of moisture-sensitive media, and the physical support of a temporary facing. Molten CDD was applied together with a facing layer of non-woven polyester, thus serving three functions at once and allowing the paintings to receive treatment with minimised risk. Item Open AccessCyclododecane: how dangerous is it?(University of Cambridge Museums, 2018-11-01) Adlem, Martin; Rozeik, ChristinaThis paper summarises a short presentation delivered at the conference ‘Volatile Binding Media in Heritage Conservation’. The author, a health and safety advisor, was asked to comment on the safety of cyclododecane (CDD) to human health, given recent debate about this issue. This paper discusses the possible routes of exposure to CDD for conservators, and looks at these in the light of known safety data. The author concludes that CDD is not hazardous to use. Item Open AccessMicroscopic observations to track the behaviour of cyclododecane crystallisation and the effect of crystal formation on fragile porous substrates(University of Cambridge Museums, 2018-11-01) Peters, Nicole; Shugar, Aaron; Skinner, Lucy; Ploeger, Rebecca; Ravines, Patrick; Rozeik, ChristinaThe objective of this project is to observe the formation and changing structure of CDD crystals and their effect on painted porous surfaces. To investigate the interaction of CDD with absorbent and weak substrates, mock-ups of fragile painted plaster were prepared and CDD was applied to each of the mock-ups as either a hot melt or dissolved in Stoddard solvent. Time-lapse microphotography recorded the behaviour of the CDD crystals regularly over a span of six weeks. Scanning electron microscopy and confocal microscopy were utilised before application and after sublimation of CDD to characterise the surface morphology and porosity of the substrate, and to observe any damage that the CDD crystals may have caused to the surface of the artefact. Three computations were used in conjuction with confocal microscopy in order to analyse the topographic deviations caused by CDD interaction: surface subtraction, profile extraction, and horizontal contour extraction. It was concluded that CDD may be altering the original surface of the samples by widening pre-existing cracks, altering particle morphology, and inducing minor elevation changes in the overall topography. However, it does not impart a new texture to the plaster nor does it appear to cause new or original cracks in the substrate. Item Open AccessVisualising cyclododecane on porous materials using cryogenic scanning electron microscopy(University of Cambridge Museums, 2018-11-01) VonStein Murray, Courtney; Stein, Renée; Taylor, Jeannette; Rozeik, ChristinaSince its introduction in the mid-1990s, cyclododecane (CDD) has found increasing use in the field of conservation. However, the physical effects of deposition and sublimation remain somewhat unexplained. This study used cryogenic scanning electron microscopy (cryo-SEM) to explore the physical interaction of cyclododecane with porous substrates commonly encountered among cultural materials: paper, wood and clay. It aimed to visualise whether the consolidant lined or filled pores, as well as whether it formed a uniform coating or an open network within pores. Comparing images of untreated and treated clay, wood, and paper samples reveals that the CDD forms a fairly uniform coating that closely mimics the topography of the substrate. Cracking and delamination of the coating was sometimes observed and may be related to the plunge-freezing process. Cryo-SEM proved limited in its ability to peer into the pores of the treated substrates because the cryogenic stage does not offer enough rotation samples themselves were too small to be easily manipulated and/or cross-sectioned, particularly while maintaining frozen conditions. Because only the topmost sample surfaces were observed, it was not possible to assess the depth of consolidant penetration or the force exerted by the consolidant upon the substrate. This study permitted an assessment of the physical interaction between CDD and the surfaces of treated substrates, revealing a close correspondence and suggesting thorough coverage of porous materials when the consolidant is applied as a saturated solvent solution. Item Open AccessUsing fluorochromised gelatine to visualise the sealing effect of cyclododecane during re-adhesion of flaking paint on canvas(University of Cambridge Museums, 2018-11-01) Soppa, Karolina; Rozeik, ChristinaWhen working with low viscosity adhesives on canvases without a sizing layer, it is advisable to mask the canvas prior to consolidation (for example with CDD solutions). The use of fluorochrome-labelled gelatine (type A, 180 Bloom 5% w/w in distilled water) in combination with fluorescence microscopy allows the sealing effect of various methods of cyclododecane (CDD) application to be visualised, in order to optimise the techniques for re-adhesion of flaking paint on canvas. As solvents for CDD, petroleum ether (boiling point <40 °C) and white spirit (b.p. 100–140 °C) have delivered positive results. The observed adhesion was best when using CDD in petroleum ether <40 °C. However, from a practical point of view, the handling of CDD in white spirit 100–140 °C is easier, the penetration is laterally wider and therefore the sublimation faster. Application of solid CDD either as chips or with a spray can (both worked in using a heated spatula on the reverse of the canvas) produced irregular and poorly reproducible results. There is a significant difference between the two CDD application techniques: if the paint has no contact with the canvas, the CDD solution stops at the canvas interface, whereas melts can penetrate further, embedding the fibres entirely and even filling the joints – or they do not reach the interface. A further important practical observation is that there should be no contact with the reverse of the canvas during application of the adhesive since this contact increases capillary forces, allowing the adhesive to penetrate more easily towards the other side. An open- celled foam, which is rigid enough for placing weights on the painting after application of the adhesive, proved to work well as an underlying support. Item Open AccessThe effect of several paper characteristics and application methods on the sublimation rate of cyclododecane(University of Cambridge Museums, 2018-11-01) Piotrowski, Kelli; Rozeik, ChristinaCyclododecane (CDD) is a waxy, solid cyclic hydrocarbon (C 12 H 24 ) that sublimes at room temperature and possesses strong hydrophobicity. In paper conservation, CDD is used principally as a temporary fixative of water-soluble media during aqueous treatments. Hydrophobicity, ease of reversibility, low toxicity and absence of residues are reasons often cited for its use over alternative materials, although the latter two claims continue to be debated in the literature. The sublimation rate has important implications for treatment planning as well as health and safety considerations, given the dearth of reliable information on its toxicity and exposure limits. This study examined how the rate of sublimation from paper is affected by fibre type, sizing and surface finish as well as delivery in the molten phase and as a saturated solution in low boiling petroleum ether. The effect of warming the paper prior to application was also evaluated. Sublimation was monitored using gravimetric analysis, after which samples were tested for residues with gas chromatography with flame ionisation detection (GC–FID) to confirm complete sublimation. Results suggested that the sublimation rate of CDD is affected minimally by all of the paper characteristics and application methods examined in this study. The main factors influencing the rate appear to be the thickness and mass of the CDD over a given surface area, as well as temperature and ventilation. The GC– FID results showed that most of the CDD sublimed within several days of its disappearance from the paper surface regardless of the application method. Item Open AccessA review of the long-term use of cyclododecane at Abydos(University of Cambridge Museums, 2018-11-01) Skinner, Lucy; Kariye, Hiroko; Rozeik, ChristinaCyclododecane (CDD), first introduced at Abydos by an American conservation team in 1999, was used to block-lift archaeological wood from 5000-year-old ships. Following this success, CDD became a mainstay of the conservation tool kit, commonly used to aid block-lifting in the field and allowed to sublime in the field lab. CDD-coated artefacts have also been sealed and packed to prevent sublimation, exploiting it to consolidate objects between seasons, and allowing treatments to be completed in subsequent years. This paper is a review of treatment methodologies using CDD in the field at Abydos and discusses both successes and failures. Database records indicate that CDD has been used over 50 times at Abydos over 17 years, representing perhaps the most extensive, long-term use of CDD on archaeological sites. A programme set up in 2011 to monitor lasting effects of CDD on the artefacts is discussed and possible alternatives to CDD suggested. Finally, recommendations for post-CDD treatment and artefact storage in the field are proposed. Item Open AccessThe use of cyclododecane in Swiss archaeological contexts(University of Cambridge Museums, 2018-11-01) Tissier, Frédérique-Sophie; Rozeik, ChristinaCyclododecane (CDD) has been used since 2004 by the Archaeological Service of the Canton of Bern, Switzerland in a wide range of situations. This article summarises various practical experiences from our institution in the field as well as in the laboratory. Experiences during excavations in Basel led to the development of the ‘sandwich technique’ for block-lifting fragile artefacts, described in this paper. The long-term storage of Roman painted wall plaster lifted with CDD brought compatibility problems to light, in 14 particular with ethyl silicate. Investigating the potential contamination by CDD of samples for C dating has also been a topic of concern, as has the residue question, which has been addressed in two graduate-level projects through FTIR, GC–MS and gravimetric methods. Health and safety issues were investigated with exposure measurements that reproduced work scenarios, for example in a trench or under a fume hood depending on the application method. Finally, a flow chart for decision-making is provided as a tool to help determine whether CDD is suitable for block-lifting, especially when further treatment is required.