Article

A multi-analytical approach to the examination of nineteenth-century European wallpapers in Vasiq-Ansari House in Isfahan, Iran

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Abstract

In the nineteenth century, imported wallpapers covered interior walls of Persian palaces and mansions, of which Vasiq-Ansari House in Isfahan, Iran, exhibits very highly elaborated examples. In this study, micro-Raman spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, ultraviolet–visible spectroscopy, and light microscopy were used to identify pigments and other materials used in the wallpapers of Vasiq-Ansari House. Results indicated that chrome yellow, artificial ultramarine blue, brass metallic leaf, an organic red dyestuff (probably cochineal), and a copper-based green were used as colourants in the wallpapers. Different shades of brown were achieved by mixing various combinations of red lead, carbon black, and calcium carbonate. The white calcium carbonate was also used as a ground layer, applied to a paper support composed of bast and softwood fibres. Based on knowledge of the materials used, these wallpapers are most probably manufactured from the mid- to late-nineteenth century.

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... However, after the Safavid period, using artificial ultramarine instead of natural became common. Examples of synthetic ultramarine can be found in nineteenth-century murals in Vasiq-Ansari House in Isfahan (Holakooei et al., 2014). ...
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... The high concentration of these elements suggested the presence of brass like decorative element due to its brightness and used as a substitute for gold. This decorative compound has also been identified in other studies carried out on wallpaper belonging to the nineteenth century [25]. According to the elemental maps, a binary brass was used since, in addition to Cu and Zn, no other metal, such as aluminum, manganese, or silicon was detected. ...
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The thermal decomposition of basic lead(II) carbonate 2PbCO3·Pb(OH)2 in static air under atmospheric conditions has been studied for the first time using a combination of thermoanalytical, X-ray diffraction and Raman spectroscopic techniques. New intermediate compounds of the type 4PbCO3·3PbO and PbCO3 have been observed in addition to previously reported ones of the type 2PbCO3·PbO, PbCO3·PbO and PbCO3·2PbO. Post-decomposition studies have identified the presence of the tetragonal-to-orthorhombic phase transition in PbO. Results are also presented for the decomposition processes in nitrogen and oxygen atmospheres. Oxidative decomposition studies have shown that Pb3O4 forms in oxygen and in flowing air.
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Citation NORMAN F. BARNES, "Color Characteristics of Artists’ Pigments," J. Opt. Soc. Am. 29, 208-210 (1939) http://www.opticsinfobase.org/josa/abstract.cfm?URI=josa-29-5-208
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Article
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Article
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Article
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Identifying and distinguishing between natural textile fibres is an important task in both archaeology and criminology. Wool, silk and cotton fibres can readily be distinguished from the textile bast fibres flax, nettle/ramie, hemp and jute. Distinguishing between the bast fibres is, however, not easily done and methods based on surface characteristics, chemical composition and cross section size and shape are not conclusive. A conclusive method based on X-ray microdiffraction exists, but as the method requires the use of a synchrotron it is not readily available. In this paper we present a simple procedure for identifying the above mentioned textile bast fibres. The procedure is based on measuring the fibrillar orientation with polarised light microscopy and detecting the presence of calcium oxalate crystals (CaC2O4) in association with the fibres. To demonstrate the procedure, a series of fibre samples of flax, nettle, ramie, hemp and jute were investigated. The results are presented here. An advantage of the procedure is that only a small amount of fibre material is needed.
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3rd. ed. Earlier editions by John H. Graff. Originally published: Appleton, Wis. : Institute of Paper Chemistry, 1967.
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Sixty pigments, minerals and media have been analysed by Fourier-transform Raman (FT-Raman) microscopy in order to assemble a database of reference FT-Raman spectra for scientists working at the Arts-Science interface. An earlier library of Raman spectra compiled using visible excitation has been extended by the addition of 22 further reference spectra obtained with 780.0, 647.1, 632.8 and/or 514.5 nm excitation. The relative merits of 1064 nm and visible excitation are discussed.
Article
In the majority of the literature describing green coloured materials used on ancient painting layers (15th or 16th century), two copper greens are mainly cited: malachite [CuCOr3 x Cu(OH)2] and verdigris [Cu(CH3COO)2 x [Cu(OH)2]3 x 2H2O]. It is shown, by micro-Raman spectroscopy, that the artists were actually employing more than these two copper greens, in particular various copper sulfates, among which the most common pigment found is posnjakite [CuSO4 x 3Cu(OH)2 x H2O]. In contrast to the PIXE (particle induced X-ray emission) technique, Raman spectroscopy is a technique of choice, able to distinguish not only a copper sulfate from a carbonate or acetate but also the different sulfates themselves; in this respect, we found that the high wavenumber region (2800-4000 cm(-1)), characteristic of H2O vibrations, is of particular interest. It is also shown that numerous green areas were created with mixtures of a copper sulfate mixed with other pigments, for instance to enhance the colour depth. Finally, in some cases, no green pigment is actually employed but the colour is obtained by intimately mixing yellow and blue pigments. All these results led to a new look at the pigments which were in use on the palettes of the ancient artists.
Article
Raman micro-probe spectroscopy has been applied to the analysis of a non catalogued hand-crafted wallpaper during its restoration process. The analysis has been totally non-destructive without the necessity of taking any sample. The artwork showed a great chromatic palette having been detected the presence of calcium carbonate, Prussian blue, ultramarine blue, gypsum (CaSO4.2H2O), minium (Pb3O4), vermilion (HgS), chrome orange (CaCO3), chrome yellow (PbCrO4), barium sulphate and carbon black (C). From the spectroscopic analysis the date of its manufacturing has been set between 1828 and 1830, introduction of chrome yellow and orange, as well as artificial ultramarine blue, and 1840, when continuous industrial wallpapers were extensively manufactured in Europe.
Article
Scientific studies of the pigments used in the manufacturing process of some pigmented wallpapers are presented in this work. Non-destructive micro-Raman spectroscopy was selected for this purpose, and provides important information about how the 19th century wallpaper industry incorporated new materials in their works and designs. At the same time, analysis can help to date the samples of uncatalogued wallpapers. Chrome yellow, burnt Sienna, Prussian blue, ultramarine blue, red lead, carbon black, calcium carbonate, red iron oxide and a red organic pigment were identified. According to the palette used, as well as to the manufacturing process, the wallpapers in this study can be dated to the second half of the 19th century.
of Their Historyand FibreOpticsReflectance Holakooei et al.Multi-analytical approach to the examination of nineteenth-century European wallpapers Studies in Conservation 2013 VOL. 0 NO. 0 10 rNylander, R.C. 1981. The Choice and Use of Reproduction Wallpapers in the Historic Interior
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  • J M Pérez
Nineteenth-CenturyWallpaper. Trends in Non-DestructiveAnalysis M.,Bujdud-Pérez,J.M., of Their Historyand FibreOpticsReflectance Holakooei et al.Multi-analytical approach to the examination of nineteenth-century European wallpapers Studies in Conservation 2013 VOL. 0 NO. 0 10 rNylander, R.C. 1981. The Choice and Use of Reproduction Wallpapers in the Historic Interior. Journal of the American Institute for Conservation, 20: 150–1