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Identification of Iron Compounds in Black Surface Layer of Stone Monuments  

Publication Information
Journal of the Mineralogical Society of Korea / v.17, no.1, 2004 , pp. 75-83 More about this Journal
Abstract
Blackening on stone monuments is serious problem, because it is not only aesthetically unattractive, but also an important process in stone deterioration. Black surface layers contain often a large amounts of iron compound. Therefore it is assumed that besides another elements the iron have influence on blackening of surface. After the samples of black surface layers were collected from the stone monuments (Museumsinsel) in Berlin, Germany, especially in this study has been used Mossbauer spectroscopy in order to determine the valence and chemical composition of iron. Mineralogical and chemical analyses were carried out X-ray diffractormetry and X-ray fluorescence method on the black surface layer's samples and original stone samples. The origin of Iron compound in the black surface provides the important clue for the conservation work of stone monuments, like removing of black surface. To find it, black surface layer on white sandstone -it contains very small amount of iron compound- was compared with that on the red sandstone (Fe contains very small amount of iron compound- was compared with that on the red sandstone (Fe abundant). As a results, it is assumed that the iron in black layer on white sandstone is originated mainly from a surrounding environmental material and for the iron in black layer on the red sandstone is responsible the original stone. Even if black surface layer was removed from the red sandstone, some other conservation method should be studied beyond removing of black surface layer, because the iron can move continuously from the inner zone of original stone to surface area.
Keywords
blackening; iron compound; Mossbauer spectroscopy; origin of iron;
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  • Reference
1 Bulgini, R. (2000) Rate of formation of Black crusts on marble. Journal of Cultural Heritage, 1, 111-116.
2 Murad, E. and Johnston, H. H. (1987) Iron Oxides and Oxyhydroxides, Mossbauer Spectroscopy-Applied to Inorganic chemistry, 3, 507-582.
3 Krumbein, W. (1991) Zum Begriff Patina, seiner Beziehung zu Krusten und Verfarbungen und deren Auswirkungen auf den zustand von Monumenten. Jahresb. aus dem Forschungsprogramm Steinzerfall Steinkonservierung, 4, 215-229.
4 Leysen, L., Roekens, E., and van Grieken, R. (1989) Air-Pollution-Induced chemical decay of a Sandy-Limestone cathedral in Belgium. The Science of the Total Environment, 78, 263- 287.
5 Mahieu, B., Ladriere, J. and Desaedeleer, G. (1976) Mossbauer Spectroscopy of Airborne Particulate Matter. Jurnal de Physique, Colloque C6, 12, 37, 837-848.
6 Grassegger, G. (1994) Die Verwitterung von Natursteinen an Bauten und Baudenkmalern. Naturwerkstein und Umweltschutz in der Denkmalpflege, Ebner Verlag Ulm, 433-489.
7 Morup, S. (1987) Mossbauer Effect Studies of Microcrystalline Materials. Mossbauer Spectroscopy-Applied to Inorganic chemistry, 2, 89-123.
8 Nord, A. and Ericsson, T. (1993) Chemical Analysis of Thin Black Layers on Building Stone. Studies in Conservation, 38, 25-35.
9 Johnston, J. and Murad, E. (1987) Industrial Application of the M${\"{o}}$ssbauer Effect, M${\"{o}}$ssbauer Spectros copy-Applied to Inorganic chemistry, 3, 565p.