26/05/2013

“Diagnostic analyses for the study of materials, technique and state of preservation of a gilt and painted leather of the XVIII century” by Mannina and Lombardo (2013)

Mannina, Loredana; Lombardo, Angela, “Diagnostic analyses for the study of materials, technique and state of preservation of a gilt and painted leather of the XVIII century”, Procedia Chemistry 8 (2013) 202–211
DOI:10.1016/j.proche.2013.03.026 / PDF (ScienceDirect)

Abstract:
In this study we report on the restoration work for the gilded and painted leather from the Sanctuary of the Santissimo Crocifisso di Papardura in Enna, Italy. The work started with a historical and stylistic examination of the artwork which dates back to 18th century. The study of the leather and its decoration was deepened thanks to specific scientific analysis (such as XRF spectroscopy, Raman and SEM) in order to assure the integrity of the material during the restoration work. To this end, a diagnostic procedure was set up to provide a clear picture of constitutive materials (type of leather, silver leaf and pigments), technique, and state of preservation.

"Evaluation of the amino acid composition, structure and properties of archaeological leather" by Plavan et al (2013)

Plavan, Viktoriia; Miu, Lucretia; Gavrilyuk, Nadia; “Evaluation of the amino acid composition, structure and properties of archaeological leather”, Procedia Chemistry 8 (2013) 279–283
DOI:10.1016/j.proche.2013.03.034 / PDF (ScienceDirect)

Abstract:
Specimens of new and archaeological leather before and after restoration were investigated. It was determined that both the ageing of leather and its further restoration affect the amount of polar amino acids in the leather. TG, DTG and DTA studies of the new and archaeological leather before and after restoration allowed a conclusion to be drawn that the prevailing process in the thermal destruction of the new leather is the breakage of cross-linking formed in tanning. In its turn, the prevailing process in the thermal destruction of the restored leather is oxidation of the products of reaction between collagen and organic substances introduced during the restoration.

10/05/2013

“The effects of hydration on the collagen and gelatine phases within parchment artefacts” by Gonzalez and Wess (2013)

Gonzalez, Lee Grant; Wess, Timothy James, “The effects of hydration on the collagen and gelatine phases within parchment artefacts”, Heritage Science 1:14 (2013)
DOI:10.1186/2050-7445-1-14 / PDF (Chemistry Central)

Abstract:
This review discusses the need to understand the effects of relative humidity on parchment and the current understanding of parchment structure and hydration. It also provides a critical evaluation of the body of foregoing research investigating the effects of relative humidity on parchment artefacts. The critical evaluation shows that the current scientific evidence that can be used to inform the debate with regard to relative humidity guidelines for the preservation of parchment artefacts is insufficient, especially in the light of a greater understanding of parchment based documents when considered as composite materials comprising collagen and gelatine. The differential behaviour of collagen and gelatine (and consequently the effect on the interfaces between them) in terms of response to relative humidity changes, is proposed as a key factor to be considered for future studies. This review concludes with an analysis of the next steps required in parchment research in order to provide an informed advisory framework.