Laser-Induced Breakdown Spectroscopy in the study of degraded glass mosaics


    Eva Pospíšilová^1, David Hradil^2,3, Dana Rohanová^4, Karel Novotný^1,5, Janka Hradilová^3


  ^1Department of Chemistry, Faculty of Science, Masaryk University, Kotlářská 2, Brno, CZ-61137,
                                          Czech Republic

  ^2Institute of Inorganic Chemistry of the AS CR, v.v.i., ALMA laboratory, Husinec-Řež, CZ-25068
                                          Czech Republic

^3Academy of Fine Arts in Prague, ALMA laboratory, U Akademie 4, Prague 7, CZ-17022, Czech Republic

     ^4Department of Glass and Ceramics, Faculty of Chemical Technology, Institute of Chemical
           Technology, Prague (ICT Prague), Technická 5, 166 28  Praha 6, Czech Republic

^5 Masaryk University, Central European Institute of Technology (CEITEC MU), Kamenice 753/5, Brno,
                                     CZ-62500, Czech Republic

Key words: LIBS, depth profiling, glass, mosaics

Laser-Induced Breakdown Spectroscopy (LIBS) is a technique providing information on elemental
composition of the sample using layer-by-layer ablation and subsequent analysis. Samples of
degraded glass mosaics collected during reconstruction of a figure of Madonna from Malbork Castle,
Poland were analysed using two different LIBS devices. Thirty laser shots were applied to one point
and individual spectra were obtained for each shot. Significant elemental lines from spectra
acquired by both instruments were chosen and processed to create the depth profiles of the samples.
Calibration of the depth profile was performed applying 5, 10, 15, 20, 25 and 30 shots and
measuring the depth of the craters using a 3D optical microscope, which uses interference with
controlled change of phase to examine the topography of the sample. Determining the behaviour of
significant elements in the depth profile together with the calibration allowed examination of the
thickness of the corrosion layer.