Laser ablation-based methods in the analysis of the objects of cultural heritage


                                          Eva Zikmundová


Involving scientific methods in the examination of the objects of cultural heritage provides
important information on the material composition and the painting technique, which can lead to a
better authentication of the object and to the determination of its age and place of origin. Laser
ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) and laser-induced breakdown
spectroscopy (LIBS) enable direct analysis of solid samples without the need of previous sample
preparation and with a minimal destruction effect. In recent years, these methods have been used
frequently in the analysis of the artworks [1, 2].


One of the advantages of LIBS analysis is a good spatial resolution. A possibility of
distinguishing different layers in the multi-layered samples was studied based on the depth
profiles of the elements present in the layers. The composition of individual layers was known,
therefore, characteristic elements representing the compounds present in each layer were chosen.
Moreover, the depth and shape of the craters were examined and the average ablation rate per each
sample was estimated. Using a handheld X-ray fluorescence spectrometer as a complementary tool to
LIBS was also investigated.


LA-ICP-MS enables the quantification of both major and minor elements and the examination of the
trace element fingerprints of individual pigments which can help determine provenance and
subsequent authentication of the used materials. The aim of our study was to optimize the process
to identify and link groups of clay-based pigments to the same region of origin based on their
composition and trace element fingerprint using pelletized powdered samples, either commercially
available or gathered directly in the locations of interest. A possibility of linking these powders
with pigments contained in real painting samples was then studied.



References:


[1] B. Giussani, D. Monticelli, L. Rampazzi, Role of laser ablation-inductively coupled plasma-mass
spectrometry in cultural heritage research: A review, Analytica Chimica Acta, 635 (2009) 6-21.

[2] A. Botto, B. Campanella, S. Legnaioli, M. Lezzerini, G. Lorenzetti, S. Pagnotta, F. Poggialini,
V. Palleschi, Applications of laser-induced breakdown spectroscopy in cultural heritage and
archaeology: a critical review, Journal of Analytical Atomic Spectrometry, 34 (2019) 81-103.