https://doi.org/10.1140/epjp/s13360-021-01834-w
Regular Article
Characterization of medieval-like glass alteration layers by laser spectroscopy and nonlinear optical microscopy
1
Instituto de Química Física Rocasolano, IQFR-CSIC, C/Serrano 119, 28006, Madrid, Spain
2
Instituto de Cerámica y Vidrio, ICV-CSIC, C/Kelsen 5, Campus de Cantoblanco, 28049, Madrid, Spain
3
Instituto de Estructura de la Materia, IEM-CSIC, C/Serrano 121, 28006, Madrid, Spain
Received:
29
April
2021
Accepted:
2
August
2021
Published online:
20
August
2021
Historical glass-based objects undergo, since the time of their manufacture, different degradation phenomena that are related to their composition and to the environment to which they were exposed. Three-dimensional (3D) structural and chemical characterization of the degradation layers is important to select the most adequate conservation strategies for glass objects. Optical microscopy (OM) is the most frequently used non-destructive method to examine the surface of historical glasses; however, the 3D structural assessment of alteration layers requires applying the destructive modality of this technique to conduct a cross-sectional study. In this work, a different approach for structural and compositional characterization of alteration layers on model medieval-like glasses is presented, based on the combination of the laser spectroscopies of laser-induced breakdown spectroscopy (LIBS), laser-induced fluorescence (LIF) and FT-Raman, and the emerging, cutting edge technique of nonlinear optical microscopy (NLOM) in the modality of multiphoton excitation fluorescence (MPEF). The results obtained through this multi-analytical photonic approach were compared with those retrieved by examination of the surface and cross sections of the samples by OM and scanning electron microscopy–energy-dispersive X-ray spectroscopy (SEM–EDS). While the combination of LIBS, LIF and FT-Raman served to assess the composition of the various alteration layers, the use of MPEF microscopy allowed the non-destructive determination of the thicknesses of these layers, showing for both thickness and composition a good agreement with the OM and SEM–EDS results. Thus, the proposed approach, which avoids sample preparation, illustrates the capability of non-destructive, or micro-destructive in the case of LIBS, laser spectroscopies and microscopies for the in situ study of glass objects of historic or/and artistic value.
© The Author(s) 2021
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.