𝔖 Bobbio Scriptorium
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Biological origin of major chemical disturbances on ecclesiastical architecture studied by Fourier Transform Raman spectroscopy

✍ Scribed by M. R. D. Seaward; H. G. M. Edwards


Publisher
John Wiley and Sons
Year
1997
Tongue
English
Weight
551 KB
Volume
28
Category
Article
ISSN
0377-0486

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✦ Synopsis


Lichens, formerly considered as weathering agents in a geological context, are shown to be capable of biodeteriorating stone substrata within a relatively short time-scale. Detailed Raman spectroscopic studies have demonstrated the highly destructive properties of calcium oxalate produced by lichen thalli. Dirina massiliensis forma sorediata is capable of chemically disturbing substrata to depths of almost 2 mm in under 12 years and converting the substrata into substantial quantities of calcium oxalate. Studies of disÐgurement of English church walls assumed to have been rendered with a decorative or protective surface via restoration, have also been proved spectroscopically to be the result of this lichenÏs biodeteriorative action. 1997