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General rightsIt is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulationsIf you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: http://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. Download date: 09 May 2018Spectrochimica Acta Part A 83 (2011) 194-199 a b s t r a c tThe Breviary of Arnold of Egmond is one of the most wealthily illuminated fifteenth century manuscripts in the Northern Netherlands. The manuscript originally contained a number of full-page miniatures, which were all removed at an unknown date before 1902. The three remaining miniatures studied here, are today part of different collections, but they were brought together for an exhibition. Although several historical and art historical details of this breviary have extensively been studied, no examination of the materials used was undertaken before. Analytical techniques, such as mobile Raman spectroscopy, can be used to characterise and identify these materials in a non-invasive way. This paper presents the results of the in situ Raman analysis of three full-page miniatures of the Breviary of Arnold of Egmond. During this study, different pigments could be identified, such as lead white (2PbCO 3 ·Pb(OH) 2 ), lead-tin yellow type I (Pb 2 SnO 4 ), ultramarine (Na 8-10 Al 6 Si 6 O 24 S 2-4 ), massicot (PbO), vermilion (HgS) and red lead (Pb 3 O 4 ). Next to identification of the pigments, visual analysis was used to detect differences and similarities between the stylistic elements of the three analysed folios.

X-ray fluorescence (XRF) spectroscopy and Raman spectroscopy are preferential analytical techniques to study cultural heritage objects, since both techniques may provide complementary information in a non-destructive manner. Moreover, the application of microscopic beams allows the investigation of heterogeneous samples on the microscopic level and the study of the heterogeneity of particular samples. The micro-XRF method became already a routine analytical imaging method also because of the well-established spectrum evaluation methodology enabling specific data handling procedures. These include multivariate statistical analysis procedures such as principal components analysis (PCA) in order to explore and describe the acquired data, and clustering techniques in order to find similar pixels (or areas) in the obtained images. In the case of the micro-Raman technique, however, the usual approach is to perform a single spot analysis of only a few selected positions in order to ultimately identify the material on the basis of the comparison with Raman spectra obtained from reference materials. However, when samples are heterogeneous, imaging is still to be preferred in order to deal with the problem of sampling. With the arrival of a new micro-Raman spectrometer at the UGent laboratories, there was the need to explore the possibilities of Raman imaging. One of the most important aspects of imaging is the time needed for the analysis. Therefore, the influence of different instrumental parameters, such as resolution (low or high) and measuring time per pixel, on the quality of Raman spectra and images was investigated in order to evaluate the possibility of performing fast Raman mappings because of the need to identify the regions of interest on the art object in a more systematic manner