Article

Lead–tin mirror formation from mixtures of red lead and tin sulphide

Department of Chemical and Forensic Sciences, University of Bradford, Bradford, West Yorkshire BD7 1DP, UK.
Spectrochimica Acta Part A Molecular and Biomolecular Spectroscopy (Impact Factor: 2.13). 09/2003; 59(10):2291-9. DOI: 10.1016/S1386-1425(03)00072-6
Source: PubMed

ABSTRACT Mosaic gold, tin (IV) sulphide, is a yellow pigment which was known in antiquity but whose use was superseded by other more easily obtainable yellow pigments by the Renaissance. The identification of mosaic gold residues in a burnished golden mirror decoration on a XIIIth Century Spanish polychrome statue is important in that the first reference to the use of mosaic gold in the European literature dates from the XIVth Century, although the use of this material in China had been recorded some time before. In this paper, Raman spectroscopy, XRD and SEM are used in the analysis of the conditions required for the formation of golden mirrors using tin (IV) sulphide in admixture with dilead (II) lead (IV) tetroxide and mercury (II) sulphide. From these results, it is proposed that the major reactions are the reduction of Sn(IV) to Sn(0) with the accompanying oxidation of lead (II) oxide to lead (IV) oxide and the formation of lead (0) and lead (II) sulphide. From these results it was possible to explain the process of creation of the golden mirror from mosaic gold in the XIIIth Century.

0 Followers
 · 
86 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: This Tutorial Review shows how Raman spectroscopic and microscopic techniques are utilised for non-destructive characterisation of archaeological artefacts and provide novel information for art historians and hints at the use of ancient technologies for the production and treatment of materials and skeletal remains.
    The Analyst 11/2004; 129(10):870-9. DOI:10.1039/b407167k · 3.91 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Raman spectroscopic studies of four specimens from an important angel wall painting in need of conservation work in a medieval church have provided some information about the pigments and pigment compositions which will influence possible future preservation and restoration strategies. Excitation of the Raman spectra at 1,064 nm in macroscopic mode and at 785 nm in microscopic mode revealed that the white pigment on the angel's wings was a mixture of barytes with calcite and lead white in minor composition. Although the specimens provided were not directly associated with coloured regions of the painting, yellow and blue microcrystals were found and they were identified as chrome yellow and lazurite, respectively. Red and brown particles were identified as cinnabar/vermilion and haematite. Several green particles were also found but could not be identified. The green and blue crystals could be related to neighbouring coloured regions of the artwork and the yellow colour could be identified as a background to the angel figure. Particles of carbon were found to be dispersed throughout the specimens and can be ascribed to soot from candles, heating stoves or oil lamps providing lighting in the church. No evidence for biological deterioration was found from the spectra. The unusual pigment palette is strongly suggestive of a later date of painting than was originally believed but there is a possibility that an earlier rendition exists underneath. Following a review of the spectroscopic data, a more extensive sampling protocol is recommended, from which some stratigraphic evidence could identify the underlying plaster and possible artwork.
    Analytical and Bioanalytical Chemistry 10/2005; 383(2):312-21. DOI:10.1007/s00216-005-0012-y · 3.58 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Corrosion from the surface layer of the printing plates of ‘Guan Zi’ paper currency, Southern Song Dynasty, China, was analysed by Raman spectroscopy. The result indicates that litharge (α-PbO) and hydrocerussite (Pb3(CO3)2(OH)2) are the primary phases of the corrosion. Lead degradation mechanism and XRD analysis suggest that there is cerussite (PbCO3) in the corrosion as well. On the basis of these results preservation of the ‘Guan Zi’ plates is discussed. Copyright © 2006 John Wiley & Sons, Ltd.
    Journal of Raman Spectroscopy 08/2006; 37(8):836-840. DOI:10.1002/jrs.1511 · 2.52 Impact Factor
Show more