Analysis of art objects and other delicate samples: Is XRF really nondestructive?

Abstract

XRF is generally considered a nondestructive analytical method in the sense that a specimen is not altered by the analytical procedure. This study is related to paintings and illuminated manuscripts, where the analytes are often inorganic pigments embedded into organic matrices such as fabrics (canvases), paper or parchment, binders, and varnish. We found that a typical measurement cycle with conventional tubes and energy dispersive systems (e.g., 100 s, 100 W tube-power) causes no visible harm. However, 3 kW radiative power for several minutes and more (as often required for wide angle scans as well as for the analysis of light elements or traces in a wavelength dispersive spectrometer) can leave visible traces of permanent yellowing, brittleness, and even mechanical decomposition. In such cases scanning electron microscopy-images indicate permanent alteration of the cellulose fibers and, in paper, of the binder. Employment of modern X-ray optical devices which focus the photons of a wide beam onto a small spot may also leave visible (and invisible) traces of destruction.

Quantitative analysis of alloys and glasses by a calibration-free method using laser-induced breakdown spectroscopy

“…For the analysis of precious and archaeological samples, LIBS can compete with X-ray fluorescence [39], which sometimes is not really nondestructive [40]. LIBS may be very close to the nondestructive mode because of the minimum possible ablated mass.…”

Millefiori glasswork technique in the Migration Period: Investigation of beads with the use of nondestructive X-ray fluorescence micro-analysis

“…X-ray fluorescence analysis (XRF) has been chosen as the most suitable analytical techniques because it is quick, reliable, nondestructive (Mantler and Klikovits, 2004) and it can be applied to irregularly shaped objects (Rindby et al, 1996;Trojek, 2012). All analyses were performed with a micro-XRF device constructed at the Czech Technical University in Prague.…”

Possible Radiation-Induced Damage to the Molecular Structure of Wooden Artifacts Due to Micro-Computed Tomography, Handheld X-Ray Fluorescence, and X-Ray Photoelectron Spectroscopic Techniques

“…The construction techniques used for these important cultural heritage artifacts have been investigated using synchrotron-based X-ray tomography (Reischig et al, 2009) and, more recently, micro-X-ray computed tomography (μCT) was carried out at Sustainable Archaeology, The University of Western Ontario (London, Ontario) on a collection of prayer beads from the Thomson Collection at the Art Gallery of Ontario (Ellis et al, 2012). While X-ray analysis of cultural heritage objects is now widely used (Bergmann, 2007;Dik et al, 2008;Garside and O'Connor, 2007;Janssens et al, 2000;Janssens et al, 2010;Mantler and Klikovits, 2004), surprisingly little work has been undertaken on possible radiation damage to artifacts during analysis (Bergmann et al, 2012;Grubb, 1974;Hoffmeyer and Hanna, 1989;Richards et al, 2012). Furthermore, Bergmann et al (2012, 365) specifically state that "X-ray techniques are generally non-destructive at sufficiently low doses.…”