Troalen L.G.,United Road Services |
Rohrs S.,Rathgen Forschungslabor Staatliche Museen zu Berlin |
Kunz S.,Rathgen Forschungslabor Staatliche Museen zu Berlin |
del Hoyo-Melendez J.M.,Laboratory of Analysis and Non Destructive Investigation of Heritage Objects
Microchemical Journal | Year: 2016
Non-European dyed materials other than textiles have received comparatively little systematic analysis, this is particularly true for objects made with dyed porcupine quills. This paper presents a comprehensive study of a group of Athapaskan porcupine quill specimens collected in 1862 which are held within the collections of National Museums Scotland, UK. Due to sampling limitations micro-destructive testing, or non-invasive analysis using PDA-UPLC, Raman Spectroscopy and PIXE were used to characterise the dye sources and metallic mordants. RBS was used to obtain additional information on the depth-profiling of the mordants in the keratin-based quill. The sensitivity of the quill specimens to photo-degradation was evaluated using Micro Fade Testing (MFT). The results from this multi-analytical study will be used to inform future display regimes of this unique collection. © 2015 The Authors.
Wang N.,Xi'an Jiaotong University |
He L.,Xi'an Jiaotong University |
Egel E.,Rathgen Forschungslabor Staatliche Museen zu Berlin |
Simon S.,Rathgen Forschungslabor Staatliche Museen zu Berlin |
Rong B.,Emperor Qin Terra Cotta Warriors and Horses Museum
Microchemical Journal | Year: 2014
The gilding and painting techniques for the clay-based polychromic sculptures in Jizo Hall of Chongqing Temple, Shanxi Province of China, are analyzed by complementary techniques of microscopy, environmental scanning electron microscopy (ESEM), energy dispersive X-ray mapping (EDX), micro-Raman spectroscopy (μ-RS), and Fourier transform infrared spectroscopy (FTIR) with a reasonable sequence. 7 gilded samples and 6 pigmented samples are collected from Jizo Hall. For the 7 gilded polychromic samples, drying oil-based, Chinese lacquer-based and glue-based "Jin Jiao" techniques are identified respectively according to their different adhesive layers used for jointing gold leaf to the preparation layer. But the presence of a copper foil top surface, as well as the inner layers with crocoites (PbCrO4) and modern red pigment in one alleged gilded polychromic sample indicate a later restoration work. Among them, two gold layers have been identified in 4 samples due to the regilded work in history. For 6 pigmented samples, painting layer is generally applied on a white preparation layer made of kaolinite or the mixture of kaolinite and gypsum. Atacamite, cinnabar, minium, yellow ochre and gypsum are identified as the main pigments, and the protein-based material is confirmed as the binding medium for red pigments. This research not only reveals the Chinese traditional gilding and painting techniques employed in polychromic sculptures of Jizo Hall, but also demonstrates the advantages and limitations of each analytical technique for identifying polychromic samples, and the necessity of complementary analytical techniques approach. © 2013 Elsevier B.V.