title: Non-Invasive and Non-Destructive Examination of Artistic Pigments, Paints, and Paintings by Means of X-Ray Methods.
abstract: Recent studies are concisely reviewed, in which X-ray beams of (sub)micrometre to millimetre dimensions have been used for non-destructive analysis and characterization of pigments, minute paint samples, and/or entire paintings from the seventeenth to the early twentieth century painters. The overview presented encompasses the use of laboratory and synchrotron radiation-based instrumentation and deals with the use of several variants of X-ray fluorescence (XRF) as a method of elemental analysis and imaging, as well as with the combined use of X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS). Microscopic XRF is a variant of the method that is well suited to visualize the elemental distribution of key elements, mostly metals, present in paint multi-layers, on the length scale from 1 to 100 μm inside micro-samples taken from paintings. In the context of the characterization of artists' pigments subjected to natural degradation, the use of methods limited to elemental analysis or imaging usually is not sufficient to elucidate the chemical transformations that have taken place. However, at synchrotron facilities, combinations of μ-XRF with related methods such as μ-XAS and μ-XRD have proven themselves to be very suitable for such studies. Their use is often combined with microscopic Fourier transform infra-red spectroscopy and/or Raman microscopy since these methods deliver complementary information of high molecular specificity at more or less the same length scale as the X-ray microprobe techniques. Since microscopic investigation of a relatively limited number of minute paint samples, taken from a given work of art, may not yield representative information about the entire artefact, several methods for macroscopic, non-invasive imaging have recently been developed. Those based on XRF scanning and full-field hyperspectral imaging appear very promising; some recent published results are discussed.
authors.affiliation: AXES Research Group, Department of Chemistry, University of Antwerp, Antwerp, Belgium. koen.janssens@uantwerpen.be.
authors.forename: Koen
authors.identifier: http://orcid.org/0000-0002-6752-6408
authors.initials: K
authors.lastname: Janssens
authors.affiliation: AXES Research Group, Department of Chemistry, University of Antwerp, Antwerp, Belgium.|Conservation/Restauration Department, University of Antwerp, Antwerp, Belgium.
authors.forename: Geert
authors.initials: G
authors.lastname: Van der Snickt
authors.affiliation: AXES Research Group, Department of Chemistry, University of Antwerp, Antwerp, Belgium.
authors.forename: Frederik
authors.initials: F
authors.lastname: Vanmeert
authors.affiliation: AXES Research Group, Department of Chemistry, University of Antwerp, Antwerp, Belgium.
authors.forename: Stijn
authors.initials: S
authors.lastname: Legrand
authors.affiliation: AXES Research Group, Department of Chemistry, University of Antwerp, Antwerp, Belgium.
authors.forename: Gert
authors.initials: G
authors.lastname: Nuyts
authors.affiliation: AXES Research Group, Department of Chemistry, University of Antwerp, Antwerp, Belgium.|Laboratoire d'Archéologie Moléculaire et Structurale, Pierre and Marie Curie, Paris, France.
authors.forename: Matthias
authors.initials: M
authors.lastname: Alfeld
authors.affiliation: AXES Research Group, Department of Chemistry, University of Antwerp, Antwerp, Belgium.|Department of Chemistry, Biology and Biotechnologies, Centro SMAART and CNR-ISTM, University of Perugia, Perugia, Italy.
authors.forename: Letizia
authors.initials: L
authors.lastname: Monico
authors.affiliation: AXES Research Group, Department of Chemistry, University of Antwerp, Antwerp, Belgium.|Royal Museum of Fine Arts, Brussels, Brussels, Belgium.|Royal Institute for Cultural Heritage, Brussels, Belgium.
authors.forename: Willemien
authors.initials: W
authors.lastname: Anaf
authors.affiliation: AXES Research Group, Department of Chemistry, University of Antwerp, Antwerp, Belgium.|Experimental Division, European Synchrotron Radiation Facility, Grenoble, France.
authors.forename: Wout
authors.initials: W
authors.lastname: De Nolf
authors.affiliation: AXES Research Group, Department of Chemistry, University of Antwerp, Antwerp, Belgium.|Royal Institute for Cultural Heritage, Brussels, Belgium.
authors.forename: Marc
authors.initials: M
authors.lastname: Vermeulen
authors.affiliation: EMAT Research Group, Department of Physics, University of Antwerp, Antwerp, Belgium.
authors.forename: Jo
authors.initials: J
authors.lastname: Verbeeck
authors.affiliation: AXES Research Group, Department of Chemistry, University of Antwerp, Antwerp, Belgium.
authors.forename: Karolien
authors.initials: K
authors.lastname: De Wael
mesh_terms: D010151:Paintings; D010858:Pigmentation; D013052:Spectrometry, X-Ray Emission; D017356:Synchrotrons; D014961:X-Ray Diffraction; D014965:X-Rays
keywords: Paintings; Pigments; Synchrotron radiation; X-ray absorption; X-ray diffraction; X-ray fluorescence