Showing papers in "Studies in Conservation in 1978"
TL;DR: In this article, the authors investigated the mechanisms by which chlorides are removed from marine iron artifacts during washing processes and found that the best chloride extraction was found to occur in those treatments which involved chemical reduction of the corrosion product.
Abstract: The mechanisms by which chlorides are removed from marine iron artifacts during washing processes were investigated. By comparing the decomposition rates of FeOCl and the chloride extraction rates it was shown that, under most conditions, the chloride removal process is diffusion controlled. The implications of this were examined and it was established that the treatment times depend on a number of factors which can vary greatly, both between artifacts from different shipwrecks and also those from the same wreck. This variation must be taken into account when comparing the efficiencies of different washing techniques. A method for evaluating relative efficiencies was devised and used to compare different standard treatment procedures. The best chloride extraction was found to occur in those treatments which involved chemical reduction of the corrosion product.
77 citations
TL;DR: The use of benzotriazole has been used for 10 years for the treatment of antiquities made of copper and copper alloys as discussed by the authors and its chemistry and theories regarding its mode of action are reviewed, and a bibliography of published work is given.
Abstract: Benzotriazole has now been in use for 10 years for the treatment of antiquities made of copper and copper alloys. Its chemistry and theories regarding its mode of action are reviewed, and a bibliography of published work is given.
62 citations
TL;DR: The sources and chemistry of waxes likely to be encountered in art objects are briefly reviewed and their gas-chromatograms are illustrated in this article, where examples of the identification of wax and wax-mixtures in a variety of objects are described, and the advantages for this purpose of gaschromatography over infrared spectroscopy are indicated.
Abstract: The sources and chemistry of waxes likely to be encountered in art objects are briefly reviewed and their gas-chromatograms are illustrated. Examples of the identification of waxes and wax-mixtures in a variety of objects are described, and the advantages for this purpose of gas-chromatography over infrared spectroscopy are indicated.
40 citations
TL;DR: A complete treatise on the technique and conservation of mural paintings can be found in this article, with a glossary of technical terms, lists of solvents, cleaning products and adhesives, and extracts from literary sources on the history of painting techniques.
Abstract: Complete treatise on the technique and conservation of mural paintings. Contents: Methods of examination and documentation, technology of materials, pigments, history of painting techniques, causes of deterioration, fixative and consolidation, transfer, new supports, cleaning and disinfection, exhibition problems. In appendix: glossary of technical terms, lists of solvents, cleaning products and adhesives, and extracts from literary sources on the history of mural painting techniques. -- AATA
30 citations
TL;DR: The uses, composition and properties of adobe are briefly reviewed and the processes contributing to the deterioration of ADobe structures are assessed in this paper, where the authors suggest that understanding of these processes must precede selection of effective preservation methods.
Abstract: The uses, composition and properties of adobe are briefly reviewed and the processes contributing to the deterioration of adobe structures are assessed. Understanding of these processes must precede selection of effective preservation methods.
28 citations
TL;DR: A white deposit was observed on the glass lids of boxes used to store archaeological textile fragments for some 40 years, which was identified as sodium formate formed from formaldehyde given off by cardboard in the boxes as discussed by the authors.
Abstract: A white deposit was observed on the glass lids of boxes used to store archaeological textile fragments for some 40 years. It was identified as sodium formate formed from formaldehyde given off by cardboard in the boxes. Heavy metal ions in some samples of the deposit originated, via the textile fragments, from corroded bronze ornaments in the graves.
23 citations
TL;DR: In this paper, a procedure was perfected that reproduces the structure and composition of original patinas, and the most common methods of treatment were applied on test samples thus prepared and on archaeological items.
Abstract: In order to test some of the methods of archaeological bronze conservation, a procedure was perfected that reproduces the structure and composition of original patinas. Then the most common methods of treatment were applied on test samples thus prepared and on archaeological items. This experiment has allowed us to choose the best treatment in accordance with the following requirements: restraint of corrosion, speed of operation, lack of colour alteration and avoidance of break-up or solution of patina.
20 citations
TL;DR: In this paper, a structure was built to keep snow and rain off the wood but which allowed air to pass over it, and the structure was covered with polyethylene sheet to allow the sun to shine on the wood surface and heat it.
Abstract: The winter climatic conditions of much of Canada provide an ideal environment for freeze-drying. We have been attempting to use these conditions for the drying of large waterlogged timbers. In the freeze-drying process the wood is kept in a frozen state and the drying proceeds by sublimation. We are particularly concerned with the treatment of large timber which present great difficulties when treated by the accepted methods. A structure was built to keep snow and rain off the wood but which allowed air to pass over it. The structure was covered with polyethylene sheet to allow the sun to shine on the wood surface and heat it. Weight changes in the wood were measured with a load transducer and temperature wa followed with thermocouple probes. Temperature and relative humidity of the surrounding air were recorded instrumentally. The timbers were of several varieties of wood in various states of decomposition. All of the wood dried quickly and much of the water was removed. This technique appears to...
17 citations
TL;DR: A detailed technological and scientific examination was carried out on a terracotta relief sculpture of the Madonna and Child attributed to the School of Verrocchio which had been in the Birmingham Museum and Art Gallery since 1895 but never previously examined in detail as mentioned in this paper.
Abstract: A detailed technological and scientific examination was carried out on a terracotta relief sculpture of the Madonna and Child attributed to the School of Verrocchio which had been in the Birmingham Museum and Art Gallery since 1895 but never previously examined in detail (although one authority had dismissed it as a nineteenth century copy). Initial examination revealed that it had been heavily over-restored in the nineteenth century. All these additions were removed during cleaning. The original terracotta relief was examined in great detail and this established the stages and techniques used in its construction and showed that it was an original piece of sculpture and not a copy. Thermoluminescence dating proved that the relief was made between 1416 and 1546 and a comparison of composition and style suggests that a date in the 1460s is appropriate.
9 citations
TL;DR: A series of corroded stone specimens from Salzburg monuments was examined by electron-probe microanalysis as mentioned in this paper, showing that the crusts arose from environmental effects, in the case of marble primarily from SO2.
Abstract: A series of corroded stone specimens from Salzburg monuments was examined by electron-probe microanalysis. The crusts arose from environmental effects, in the case of marble primarily from SO2. Deterioration phenomena can be correlated with stone surface features.
9 citations
TL;DR: In this paper, the Beta method is used to identify three types of wood: completely decayed wood, attacked wood and sound wood, and the problem of shearing off means collapse.
Abstract: The horizontal components of historical buildings (roof, floors) are, in general, timber constructions. These horizontal constructions carry loads (pan-tiles, slates, wind, snow, furniture, people, etc.). The vertical components (walls) carry the horizontal, so the bearings of floors and roof constructions transfer the loads to the walls. In principle these transfer points are the beam-ends. Timber decay of these beam-ends means a risk of collapse, when the bearings are not able to transfer the 10'ads. In principle we can distinguish three zones (Fig. 1): A: completely decayed wood B: attacked wood C: sound wood. The problem is zone B, because shearing off means collapse. The basic principle of the Beta method is to remove zones A and B (Fig. 2). Holes are drilled (Fig. 3), diameter 28 mm, reinforcement rods, diameter 20 mm, are inserted (Fig. 4) and the remaining cavities filled with a mortar of grit,
TL;DR: Buck's approach was to measure acoustical variations between supported and unsupported paint films by means of a phonograph cartridge as mentioned in this paper, and he enthusiastically supported the project when I began my own research into void detection.
Abstract: IN APPRECIATION OF RICHARD D. BUCKt Richard D. Buck was instrumental in my investigation of techniques for detecting voids in panel paintings. When I first mentioned the topic of void detection to Mr Buck in 1973 I was not surprised to learn that he had attempted to devise a void detection technique decades before at the Fogg Art Museum. At that time his approach was to measure acoustical variations between supported and unsupported paint films by means of a phonograph cartridge. When I began my own research into void detection, Mr Buck enthusiastically supported the project. For Richard Buck, no idea was too odd or unlikely to deserve attempt. Not only did he love new ideas, he was indefatigable in his attempt to try them out. In Richard Buck's memory I present the following paper.
TL;DR: Two Court mantuas and petticoats of the early eighteenth century, embroidered in silver thread, which had been extensively altered, were cleaned and mounted in their original form for museum display.
Abstract: Two Court mantuas and petticoats of the early eighteenth century, embroidered in silver thread, which had been extensively altered, were cleaned and mounted in their original form for museum display. Techniques involved in this included securing and cleaning the silver embroidery, support of the original lining on a net treated with polyvinyl acetate emulsion, and the final support and mounting of the costume for museum display.
TL;DR: The action of stripping agents on exposed bronze alloys was studied in this article, where two degrees of etching were found to occur before the times normally recommended for treatment had elapsed.
Abstract: The action of 'stripping' agents on exposed bronze alloys was studied. Test pieces of tin-bronze and leaded tin-bronze alloys having compositions typical of ancient objects were cast from modern metal stock, simulating procedures used in antiquity, and subjected to the following reagents: alkaline glycerol, alkaline Rochelle salt, Calgon, citric acid and buffered citric acid solutions. The effects on the metal were studied by using metallographic techniques and monitoring pH readings. Two degrees of etching were found to occur before the times normally recommended for treatment had elapsed. The pH of the solutions showed a slight change.
TL;DR: An environmentally controlled case for conserving a Fayum panel painting on loan to the Brooklyn Museum was described in this paper, where the case was constructed of aluminium with a glass front, sealed in an air-tight fashion with a gasketted metal frame.
Abstract: An environmentally controlled case is described for conserving a Fayum panel painting on loan to the Brooklyn Museum which exhibited a high degree of sensitivity to changes in relative humidity. The case was constructed of aluminium with a glass front, sealed in an air-tight fashion with a gasketted metal frame. It was intended to maintain a level of 50% RH in order to relax the panel painting from its high degree of warping, returning it to its original contour, and to conserve it permanently in this micro-climate. The humidity control agent found very satisfactory for this purpose was silica gel pre-conditioned to produce the 50% RH environment. The method of preparation of the gel was by exposure over a saturated solution of magnesium nitrate hexahydrate. The authors have detailed the construction of the case and method of installation of the Fayum portrait, as well as the technique of silica gel maintenance. The interior climate has been controlled satisfactorily since November 1974.
TL;DR: In this article, the authors used hot animal glue solutions for the consolidation of wood-boring insects and fungi in order to prevent further decay of wood objects, such as sculptures and ethnographical artifacts.
Abstract: Wooden objects, such as sculptures and ethnographical artifacts, attacked by the action of wood-boring insects and fungi have been treated traditionally with a great variety of materials [1]. This is relevant to the consolidation of affected parts as well as to the prevention of further decay. One of the oldest known techniques is the consolidation with hot animal glue solutions. This method" which was developed in the beginning of the century, does have some advantages. Hot animal glue solutions can be applied in rather high concentrations up to 40-50%, yet they have a low viscosity of about 5-7 cP, which theoretically favours consolidation as well as penetration. Unfortunately, however, there are many drawbacks to this method. The glue itself is very susceptible to attack from fungi and insects and the penetration is insufficient because of premature gelling of the solution on' cooling to 35--45°C. Besides, stresses may arise through swelling and shrinkage of the wood due to the action of water. Results with different kinds of wax were also unsatisfactory. Mineral, vegetable, and animal types of wax (microcrystalline, camauba and beeswax) may considerably discolour the surface of the object and will only penetrate superficially. Subsequent glueing or grounding of wax-treated parts also becomes impossible, and the treatment in baths with molten wax at 70-100°C may severely damage polychromy and gilt-work. Another unsuccessful method is the treatment with drying ails, such as linseed or-tung oil, possibly mixed with natural resins. This method fails because of insufficient curing of these materials due to a lack of oxygen, needed for the reaction, in the interior of the object. The' consolidation method which is usually employed is the iInpregnatton with solutions of natural or synthetic resins. In this respect the natural resins such as rosin, dammar, mastic and shellac indeed have certain advantages due to their low molecular weight allowing high concentrations at low viscosity [2]. Synthetic polymers, which are mostly applied for this purpose, show much'higher viscosities at comparable concentrations. In general, however, ~olutions are not ideal for consolidation. In the first place most solvents are swelling agents for paint and may eventually damage polychromy and gilt-work. Another property which may affect the results is the enrichment of polymer at the surface of the impregnated object after treatment, either due to evapor4tion of solvent and subsequent transport of more solution to the surface, or to i'nitial chromatographic processes. This effect can be offset by slowing down the evaporation through wrapping the object in plastic foil, in this way allowing a transport of polymer back into the object by diffusio~ [3]. On biggero!,jects, however, this cannot be done. As stated earlier, the synthetic polymers can only be employed in a diluted form (10-20%) to minimize the viscosity. This means, however, that mairily solvent is introduced, making a repeated treatment necessary to get sufficient consolidation. The evaporation of solvent may also be harmful to the object because of shrinkage stresses which it may produce. Working with large quantities of organic solvent may moreover present health and fire risks. Finally the chemically or radiatiort(4] curing synthetic polymers, such as epoxy, polyester, acrylic and polyJlrethane resins should be mentioned. Advantages of these materials are that they can be applied without solvents, that they have a negligible shrinkage on curing and that they are versatile with regard to curing time and properties 'of the finished product. The high viscosity of these materials, however, limits their application for the impregnation of porous materia\s. Dilution of polyesters or acrylic systems with solvents or solvent-like monomers such as styrene or Ill:ethyl methacrylate introduces the usual adverse effects mentioned above, especially with regard topaint layers. The same holds true for epoxy resins. Common commercial epoxy resin (bisphenol A diglycidyl ether):
TL;DR: In this paper, the authors present a survey of the conservation of wood in painting and the decorative arts, pp. 141-144, Preprints of the Contributions to the Oxford Congress, 17-23 September 1978.
Abstract: (1978). HOLOGRAPHIC INTERFEROMETRY OF PAINTED SURFACES. Studies in Conservation: Vol. 23, Preprints of the Contributions to the Oxford Congress, 17-23 September 1978. Conservation of Wood in Painting and the Decorative Arts, pp. 141-144.
TL;DR: In this paper, the effect of relative humidity on wood in painting and the decorative arts is discussed. But the focus is on the relationship between wood and relative warmth, and not on the conservation of wood.
Abstract: (1978). THE DIMENSIONAL RESPONSE OF WOOD TO VARIATION IN RELATIVE HUMIDITY. Studies in Conservation: Vol. 23, Preprints of the Contributions to the Oxford Congress, 17-23 September 1978. Conservation of Wood in Painting and the Decorative Arts, pp. 1-6.
TL;DR: In this article, two different cleaning methods were found necessary to remove silver chloride corrosion products from different areas of a silver canopic vessel containing about 6% of copper, and two possible mechanisms of silver corrosion which could have led to the differing cleaning methods are put forward.
Abstract: Two different cleaning methods were found necessary to remove silver chloride corrosion products from different areas of a silver canopic vessel containing about 6% of copper. Two possible mechanisms of silver corrosion which could have led to the differing silver chloride corrosion products are put forward.
TL;DR: In this paper, a method to create a solid, reinforced foundation for weakened leather, using a fiberglass base, was proposed to protect the artifact from damage caused by pokes, bumps, or excessive pressure.
Abstract: A method to create a solid, reinforced foundation for weakened leather, using a fiberglass base. This procedure protects the artifact from damage caused by pokes, bumps, or excessive pressure.
TL;DR: In this paper, the authors describe the decay and restoration of treemopes at island sites on the North Pacific coast of the United Kingdom, and discuss conservation of wood in painting and the decorative arts.
Abstract: (1978). THE DECAY AND RESTORATION OF TOTEM POLES IN SITU AT ISLAND SITES ON THE NORTH PACIFIC COAST. Studies in Conservation: Vol. 23, Preprints of the Contributions to the Oxford Congress, 17-23 September 1978. Conservation of Wood in Painting and the Decorative Arts, pp. 117-122.
TL;DR: A painting by A. Jorn on masonite board was badly damaged by fire and was impregnated from the back with an acrylic binder by means of vacuum as discussed by the authors.
Abstract: A painting by A. Jorn on masonite board was badly damaged by fire. It was impregnated from the back with an acrylic binder by means of vacuum. The blisters were then laid using a vacuum hot-table at 75°C, the introduced acrylic acting as adhesive.
TL;DR: In this article, the use of B72 in the restoration of a marquetry surface is discussed, and a case history of its use in conservation is presented. But the case is not discussed in detail.
Abstract: (1978). USE OF B72 IN THE RESTORATION OF A MARQUETRY SURFACE—CASE HISTORY. Studies in Conservation: Vol. 23, Preprints of the Contributions to the Oxford Congress, 17-23 September 1978. Conservation of Wood in Painting and the Decorative Arts, pp. 37-39.
TL;DR: A stainless steel tank for polyethylene glycol treatment of waterlogged wood is described in this paper, which can be used for other purposes while the circulating pump and filter unit can be detached and used with other tanks.
Abstract: A stainless steel tank for the polyethylene glycol treatment of waterlogged wood is described. The unit is designed to function semi-automatically and with the minimum of maintenance, and also to improve on the standard method of treatment. The tank can also be used for other purposes while the circulating pump and filter unit can be detached and used with other tanks.