"Leather material found on a 6th B.C. Chinese bronze sword: a case study" by Luo et al (2011)

Luo, W.; Si, Y.; Wang, H.; Qin, Y.; Huang, F.; Wang, C.; "Leather material found on a 6th B.C. Chinese bronze sword: a case study", Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 79(5) (2011) 1630-1633

doi:10.1016/j.saa.2011.05.023 (restricted access)

Abstract:

During July to November, 2006, an important archaeological excavation was conducted in Yun country, Hubei province, southern China. Chinese archaeologists found some remnant of leather materials, covered with red pigments, on a 6th century B.C. Chinese bronze sword. To understand the technology/ies that may have been utilized for manufacturing the leathers, a combined of Raman spectroscopy, FT-IR and XRF was thus applied to the remnant of leather materials. Raman analyses showed that red pigment on the leather was cinnabar (HgS). FT-IR and XRF analyses indicated that the content of some elements, such as Ca (existing as CaCO₃) and Fe (existing as Fe₂O₃), were much higher than those in the surrounding grave soil. The results inferred an application of lime depilation and retting, and the Fe–Al compound salt as tanning agent. And it was furthermore implicated that the Fe–Al salt tanning technique had been developed in the middle and late Spring and Autumn Period of China.

Purse, 1630, The MET Museum of Art

Pilot aviation helmet, 1918-19, National Postal Museum, Smithsonian Institution

SI Collections Search Center: Pilot Edward Gardner’s aviation helmet

"Tannins characterisation in new and historic vegetable tanned leathers fibres by spot tests" by Falcão and Araújo (2011)

Falcão, L.; Araújo, M. E. M.; "Tannins characterisation in new and historic vegetable tanned leathers fibres by spot tests", Journal of Cultural Heritage 12(2) (2011) 149-156

doi:10.1016/j.culher.2010.10.005 (restricted access)

Abstract: 

This paper describes the adaptation and evaluation of three chemical tests for tannins characterisation in vegetable tanned leathers. Tests were performed on fibres of new leathers tanned with different known vegetable tannins and historic leathers. Rhodanine test, nitrous acid test and acid butanol test, developed to identify, respectively, gallotannins, ellagitannins and condensed tannins, are described. Ferric test and vanillin test, the two traditional tests used for vegetable tanned leathers characterisation, were also performed and their usefulness discussed. Gallic acid, ellagic acid and catechin, structural constituents of the different classes of tannins were also tested. Results of the developed methodology allowed the identification of tannins’ chemical class in new and historic leather samples studied. Data obtained permitted to verify the information on tanning materials used in new leathers. Vegetable tanning technology was confirmed in historic samples and tannins were characterised. This study shows that these tests are useful and can be a valuable source of information to evaluate new vegetable tanned leathers quality for conservation and restoration purposes as well as historic leathers tanning technology.

Khamsa (Quintet) of Nizami, 1510, The MET Museum of Art

"Khamsa (Quintet) of Nizam [Shiraz, Iran] (13.228.6)". In Heilbrunn Timeline of Art History. New York: The Metropolitan Museum of Art, 2000–. http://www.metmuseum.org/toah/works-of-art/13.228.6 (March 2007)