Archaeometallurgy using synchrotron radiation: a review

Abstract

Archaeometallurgy is an important field of study which allows us to assess the quality and value of ancient metal artifacts and better understand the ancient cultures that made them. Scientific investigation of ancient metal artifacts is often necessary due to their lack of well-documented histories. One important requirement of analytical techniques is that they be non-destructive, since many of these artifacts are unique and irreplaceable. Most synchrotron radiation (SR) techniques meet this requirement. In this review, the characteristics, capabilities, and advantages and disadvantages of current and future SR facilities are discussed. I examine the application of SR techniques such as x-ray imaging (radiography/microscopy and tomography), x-ray diffraction, x-ray fluorescence, x-ray spectroscopy, Fourier transform infrared spectroscopy, and lastly combined SR techniques to the field of archaeometallurgy. Previous case studies using these various SR techniques are discussed and potential future SR techniques are addressed.

A prototype handheld X-ray diffraction instrument

“…Naturally, a very wide range of materials are encountered in the field as a whole and the use of HHXRD would need to be targeted to specific material types such as metallic artefacts. The application of nondestructive techniques is increasingly important in archaeometry studies (Young, 2012;Janssens et al, 2016) and instrument portability is also a crucial advantage (Chiari, 2008). Curators are reluctant to allow artefacts to leave the museum/collection and HHXRD devices could also be taken to archaeological sites to improve conservation decisions.…”

Complementary analytical methods for analysis of Ag-plated cultural heritage objects

“…potential processing methods), and an estimation of composition for the base metal. However due to the nature of synchrotron facilities, SR-XRD experiments requires transportation of objects, which can be very difficult especially for cultural objects of high value, and beam time approval [47]. In addition, although it was not performed in this study, it is also possible with aid of standards to determine grain size based on peak broadening observed in diffraction patterns [63,64] SEM/FIB also yielded valuable information such as local grain structure of the Ag-plating, local plating thickness, composition of the plated region, and a qualitative understanding of the base metal by correctly identifying Cu and Ni as major elements in the base metal, although the presence of Zn was missed.…”

“…It should also be noted that both XRD and XRF can now be performed in situ using portable devices and both have become common practices in the analytical study of cultural heritage objects [40][41][42][43][44][45][46]. Studies on the base material can be performed non-destructively using synchrotron, neutron, and proton sources available at large user facilities due to their much greater penetration depths; however, it is difficult to examine large bodies of work due to the nature of these facilities [47][48][49][50][51].…”

2013 Atomic spectrometry update—A review of advances in X-ray fluorescence spectrometry

“…Reviews of the developing use of XRF with SR excitation sources to archaeological applications were published during the current review period. Thus, Young 268 considered the characteristics, capabilities, advantages and disadvantages of SR techniques in the analysis of metal artifacts, particularly to provide a better understanding of the ancient cultures that made them. Bergmann et al 269 considered the application of recently developed SR rapid scanning techniques designed to map large objects, highlighting advantages over traditional systems and of obtaining data using other SR techniques during the same analytical session.…”