Raman and X‐ray fluorescence glaze characterisation of Maria Keil's decorative tile panels. (10th August 2020)

• Record Type: Journal Article
• Authors: Mortari, Camila; Nobre Pais, Alexandre; Esteves, Lurdes; Gago da Câmara, Alexandra; Carvalho, Maria Luísa; Manso, Marta
• Other Names: Ziemann Martin A. guestEditor.; Madariaga Juan Manuel guestEditor.
• Is Part Of: Journal of Raman spectroscopy. Volume 52:Number 1(2021)
• Page Start: 59
• Page End: 70
• Publication Date: 2020-08-10
• Subjects: decorative tiles -- glaze -- material studies -- μ‐Raman -- μ‐XRF; Raman spectroscopy -- Periodicals; 535.846
• DOI: 10.1002/jrs.5960
• Languages: English
• ISSNs: 0377-0486

Abstract

Abstract: A set of decorative contemporary tile panels, created by the Portuguese artist Maria Keil (1914–2012) for the Lisbon metro stations, was studied under a noninvasive analytical methodology. This methodology combines X‐ray fluorescence spectrometry (μ‐XRF) and Raman spectroscopy in microscopic (μ‐Raman) mode for an elemental and structural composition characterisation of the glaze (glass matrix and network modifiers such as fluxes, opacifiers and colouring agents). μ‐XRF quantitative evaluation of the glassy matrix shows that all glazes have a lead silicate glass base. Results obtained by the combined use of μ‐XRF and μ‐Raman show that a zirconium‐based opacifier was used. Naples yellow (Pb2 Sb2 O7 ), lead–tin yellow type II (Pb(Sn, Si)O3 ), Pb–Sn–Sb triple oxide, cobalt blue (CoAl2 O4 ), chromium oxide (Cr2 O3 ) and malayite sphene (CaO·SnO2 ·SiO2 ) have been identified by μ‐Raman as some of the colouring agents, either used by themselves or in mixtures for obtaining the desirable colours intended by the artist. Abstract : A set of decorative contemporary tile panels created by the Portuguese artist Maria Keil, for the Lisbon metro stations, was for the first time under a noninvasive analytical study. This study combines μ‐XRF and μ‐Raman analytical techniques for an elemental and structural composition characterisation of the tile's glazes. Results show that the artist has chosen a glassy matrix with a lead silicate glass base and a variety of pigments as well as pigments mixtures to enlarge the chromatic pallet of the glaze.