"The use of thermal analysis methods for authentication and conservation state determination of historical and/or cultural objects manufactured from leather" by Budrugeac et al (2011)

Budrugeac, P.; Cucos, A.;  Miu, L.; “The use of thermal analysis methods for authentication and conservation state determination of historical and/or cultural objects manufactured from leather”, Journal of Thermal Analysis and Calorimetry 104(2) (2011) 439-450 

DOI: 10.1007/s10973-010-1183-0  (restricted access)

Abstract:

Leather products have been useful materials since the dawn of human history. Many leathers objects are valuable treasures due to the history they represent, and their preservation challenges museum custodians and private collectors alike. In this article, the applications of thermal analysis methods (Micro Hot Table (MHT), thermogravimetry/derivative thermogravimetry (TG/DTG), dynamic scanning calorimetry (DSC), differential thermal analysis (DTA), and dynamic mechanical analysis (DMA)) for the characterization of the recently manufactured and old leathers are presented. These methods can be used for the assessment of deterioration degree of leathers, and, therefore, the data obtained by these techniques could be useful for achievement of the suitable preservation procedures as well as the effects of conservation treatments. In addition, it was pointed out that these methods are suitable for qualitative distinction between the recently manufactured leathers and heritage items.

"Characterisation and evaluation of the environmental impact on historical parchments by DSC" by Badea et al (2011)

Badea, E.; Della Gatta, G.; Budrugeac, P.; “Characterisation and evaluation of the environmental impact on historical parchments by differential scanning calorimetry”, Journal of Thermal Analysis and Calorimetry 104(2) (2011) 495-506

DOI: 10.1007/s10973-011-1495-8 (restricted access)

Abstract:

Our recent developments concerning the assessment of parchments deterioration using DSC are reported. Measurements performed on samples in excess water conditions, in static air and gas flow provided qualitative and quantitative information on parchment ageing and deterioration at microscopic and mesoscopic level, when assembly of fibres/fibrils is weakened, partially and eventually completely lost, and at molecular level, when triple helix uncoiling occurs. A damage ranking scale based on a large collection of DSC parameters obtained by investigating artificially aged samples was set up. Deconvolution of the DSC thermal denaturation peaks in excess water enabled evaluating and discriminating stability of parchments with similar damage levels. Further experimental evidences such as softening of the crystalline fraction of collagen, thermal-oxidation and collagen gelatinisation were detected by DSC measurements in gas flow and static air, and related to specific deterioration patterns. DSC measurement of wet samples provided an objective and reliable method for evaluating parchment shrinkage temperature overcoming the limitations of conventional methods.

 

"An easy-to-build museum saddle mount" by Shevchuk (2009)

Shevchuk, Paul; "An easy-to-build museum saddle mount", Conserve O Grams 9/2 (2009)
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From the introduction:

This Conserve O Gram provides guidance on how to build a mount to support and store a large saddle with component parts (straps, stirrups) in the way it was intended to be used. This mount is strong, light-weight, and easy to move or transport, and uses cabinet space efficiently.

"Non-destructive spectroscopic characterization of parchment documents" by Bicchieri et al (2011)

Bicchieri, M.; Monti, M.; Piantanida, G.; Pinzari, F.; Sodo, A.; “Non-destructive spectroscopic characterization of parchment documents”, Vibrational Spectroscopy 55(2) (2011) 267-272

doi:10.1016/j.vibspec.2010.12.006 (restricted access)

Abstract:

Membranaceous substrates – widely found in library heritage– are truly challenging, due to the variety of manufacturing traditions, the intrinsic variability of the animal's skin and the different degradation patterns affecting documents along ageing. Moreover, when dealing with unique and delicate objects as cultural heritage specimens, sampling is never recommended and often explicitly forbidden. Aim of the research presented in this work is to achieve correct protocols for unambiguous characterization of the document's materials chemical structure and of the possible surface treatments.

Experimental results allow us to evidence that the chosen non-destructive techniques (Raman, ATR-FTIR and SEM/EDS) provide a good differentiation between parchment manufacturing procedures, western with lime and eastern with enzymatic treatment. Incrustations of salts on the surface as well as superficial treatment with tannin can be clearly detected. Origin of tannin – from the surface or in ink – can also be distinguished.

Choice of the better technique is sample-dependent, since preparation methods, degradation, presence of incrustations, amount of tannin, dehairing method can differently affect the spectral features. For instance, Raman appears to be the most effective molecular technique on western parchment, whereas ATR-FTIR allows distinguishing the enzymatic dehairing procedure from the chemical one.

Qur'an case, Nasrid period, Spain, 15th century, The Met Museum of Art

"Qur'an case [Spain] (04.3.458)". In Heilbrunn Timeline of Art History. New York: The Metropolitan Museum of Art, 2000–. http://www.metmuseum.org/toah/works-of-art/04.3.458 (October 2010)"

Leather embroidered with gilt-silver wire.

"L'évolution des différentes méthodes de tannage" par Thuau (1921)

Thuau, U.; "L'évolution des différentes méthodes de tannage", Le Cuir 10(4) (1921) 80-84
URL

"Skin tight" by McHugh (2011)

McHugh, S.; "Skin tight", The ethnographic conservation newsletter of the Working Group on Ethnographic Materials of the ICOM Committee for Conservation 32 (2011) 8-11
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Introduction:

In 2009 an unusual and complex treatment was carried out at the National Gallery of Australia on a skin covered Janiform (two faced) mask from Nigeria. Now an important part of the National Gallery’s small African collection, the Janiform mask was already in poor condition when it was acquired in 1974. As suggested by the name, it has two faces back to back, thought to be male and female, with raised designs imitating local scarification practices. It is constructed from what is believed to be antelope skin, stretched over a two part hard wood structure, and a loss to one side of the wood had caused movement and subsequent tears and losses to the skin. Testing was carried out to determine the most effective methods and materials for the necessary repairs, based on a literature search for treatments on similar materials. A brief mention in one paper of natural skin condoms caught the conservators’ attention and these eventually turned out to be the most useful material tested and key to the success of the treatment that followed.

"Dynamic mechanical analysis (DMA) of new and historical parchments and leathers.." by Cucos et al (2011)

Cucos, A.; Budrugeac, P.; Miu, L.; Mitrea, S; Sbarcea, G.; "Dynamic mechanical analysis (DMA) of new and historical parchments and leathers: correlations with DSC and XRD", Thermochimica Acta 516, Issues 1-2 (2011) 19-28
doi:10.1016/j.tca.2011.01.006 (restricted access)

Abstract:

A sort of pure collagen, 22 sorts of new parchments, 35 sorts of old (14th–19th centuries) parchments, 19 sorts of new vegetable tanned leathers and 31 sorts of old (15th–19th centuries) leathers were investigated by DMA technique in tensile mode from room temperature to 260 °C. The obtained results were correlated with those determined by DSC measurements performed in N₂ flow in the same temperature range and by XRD. It was pointed out that all collagen-based materials contain a “crystalline” region exhibiting a phase transition (“melting”) in the temperature range 210–260 °C, which is characterized by an endothermic peak in the DSC curve and an abrupt decrease of storage modulus in DMA. Differences in the parameters of this phase transition, related to various deterioration levels, were put in evidence and discussed.

Shoes, ca.1700, Victoria & Albert Museum

"Biodeterioration of archeological leather" by Strzelczyk et al (1997)

Strzelczyk, A. B.; Bannach, L.; Kurowska, A.; “Biodeterioration of archeological leather”, International Biodeterioration and Biodegradation 39(4) (1997) 301-309(9)

doi:10.1016/S0964-8305(97)00026-7 (restricted access) / PDF

Abstract:

Leather objects are frequently found in archaeological excavation. Often this material is contaminated with mineral salts which crystallize on the surface upon excavation. Unconserved finds are easily attacked by microorganisms. The microflora growing on untreated as well as conserved leather artifacts were studied. Conservation treatments investigated include: mechanical cleaning, wet cleaning, wet cleaning in Canpac solution, chemical cleaning in orthophosphoric acid, sumach retanning, Al₂(SO₄)₃ tawed, van Soest dressing, and silicone liquor.

Hat box, 1890-1899, Victoria & Albert Museum

Die Kollagenmatrix archäologischer Funde im Vergleich zu künstlich gealterten Ledermustern historischer Gerbverfahren von Bernhard Trommer (2004)

Bernhard Trommer, Die Kollagenmatrix archäologischer Funde im Vergleich zu künstlich gealterten Ledermustern historischer Gerbverfahren, PhD Dissertation, Fakultät für Werkstoffwissenschaft und Werkstofftechnologie der Technischen Universität Bergakademie Freiberg (2004)
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Abstract:

Ausgangspunkt der wissenschaftlichen Arbeit bildet eine Recherche historischer Leder- und Gerbarten. Die Quellen wurden auf ihren technologischen Wahrheitsgehalt überprüft. Dazu wurden über 30 Rezepturen historischer Gerbarten entwickelt und halbtechnisch erprobt. Im Ergebnis entstanden Referenzleder, welche analysiert und experimentell auf ihr Alterungs- und Abbauverhalten untersucht wurden. Die klassischen Methoden der Lederprüfung, die Elektronenstrahlmikroskopie (SEM/ EDX), die UV- und FT-IR-Spektroskopie, RP-HPLC- sowie die DSC-Analyse wurden für die Untersuchung der Referenzleder benutzt und weiterentwickelt. Die Erkenntnisse aus Recherche, technologischer Rekonstruktion, Simulation und Analyse wurden an archäologischen Lederfunden evaluiert. Das Alter der untersuchten Funde umfaßt eine Zeitspanne von 100 bis 3.300 Jahren. Bei der Wahl der Objekte wurde auf ein unterschiedliches Fundortmilieu Wert gelegt, um die Auswirkungen typischer Standortbedingungen auf die Ledermatrix zu erforschen. 

Coat made from salmon skin, ca.1900, Victoria & Albert Museum

"Some Notes on the Chemical Technology in an 11th Century Arabic Work on Bookbinding" by Levey et al (1956)

Levey, M.; Krek, M.; Haddad, H.; "Some Notes on the Chemical Technology in an Eleventh Century Arabic Work on Bookbinding", Isis 47 (1956) 239–243
JSTOR (restricted access)

"Appendix: Notes on the restoration of the Behaim shields" by Faltermeier & Meyer (1995)

Faltermeier, Christel; Meyer, Rudolf; "Appendix: Notes on the Restoration of the Behaim Shields", Metropolitan Museum Journal 30 (1995) 53-60
JSTOR (restricted access) | PDF

"The seven shields of Behaim: new evidence" by Nickel (1995)

Nickel, Helmut; "The Seven Shields of Behaim: New Evidence", Metropolitan Museum Journal 30 (1995) 29-51
JSTOR (restricted access)| PDF

Frame drum, 19th century, The Met Museum of Art

"Treatment and technical study of a Lakota beaded hide" by Nicole Ledoux (2010)

Nicole Ledoux, "Treatment and Technical Study of a Lakota Beaded Hide", ANAGPIC 2010 Annual Student Conference, Queen's University at Kingston Art Conservation Department (2010)
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Abstract:

This paper discusses the conservation and technical study of a Lakota (est.) beaded hide object in very poor condition. The piece, whose original function is not known, was reported as collected in the late 19th or early 20th century by John Anderson, a photographer living on the Rosebud reservation in South Dakota. It was passed down through family lines until it was recently donated to the UCLA/Getty conservation program. At some point in its history, the piece suffered liquid damage that has drastically altered more than half of the hide area, causing darkening, embrittlement, and fragmentation, as well as damage to the associated beadwork, including localized staining resulting in part from bead corrosion. In order to better understand these alterations and their implications for conservation treatment, a technical study has been undertaken that includes both morphological characterization and materials analysis of the hide and tannins. Continued work has included identification of bead composition and characterization of the various alteration products, as well as consultation with tribal and museum experts about original function and appropriate loss compensation. This object provides an interesting case study for investigating the deterioration of hide and the approach taken in treating such significantly altered material.

"Cuoi dipinti a Venezia. La carità." di Vanni Tiozzo (2003)

Vanni Tiozzo; "Cuoi dipinti a Venezia. La carità.", Dipartimento Tecniche e Restauro dell’Accademia di Belle Arti di Venezia, Venezia (2003) 51-54
URL

Dalla introduzione:

I cuoi dipinti della Carità giacevano dimenticati in un cassone dipinto nella Direzione della Accademia di Belle Arti di Venezia. Il cambio della Direzione, quando successe il prof. Riccardo Rabagliati al prof. Antonio Toniato, impose il riordino dell’ufficio e l’attenzione della dott.ssa Rita Zanchi fece rinvenire un rullo rabberciato di colore marrone dal quale si scorgeva la parte interna dipinta. La gentile signora ne parlò con l’allora decano, il prof. Mario Guadagnino, il quale, ne aveva solo un vago ricordo e propose al Direttore di affidarli al corso di restauro affinché potessero venire meglio conservati; da questo aneddoto inizia il percorso di cui ora vi diamo conto. 

Leather and leatherworking in Anglo-Scandinavian and Medieval York by Mould et al (2003)

Mould, Q.; Carlisle, I.; Cameron, E.; Leather and leatherworking in Anglo-Scandinavian and Medieval York, Vol.17: Small Finds, Fasc.16: Craft, Industry and Everyday Life, The Archaeology of York (2003)
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From the summary:

This volume, the collaborative work of a number of authors, presents the surviving evidence for the manufacture and the use of leather artefacts at York during the Anglo-Scandinavian and medieval periods. It is based around the internationally important group of Anglo-Scandinavian leatherwork from 16-22 Coppergate, along with smaller amount od medieval material recovered from the site, supplemented by groups recovered from the Coppergate watching brief, excavations at 22 Piccadilly, and at the site of the Foundry and College of Vicars Choral at Bedern. Over 5000 items of leather dating from the 9th–15th century from Coppergate and other sites in the city are represented, some 550 of which have been fully catalogued in this fascicule. The close dating of the deposits belonging to the earlier years of occupation at Coppergate makes the 9th- to 11th-century material of particular significance.