IN SITU CHEMICAL COMPOSITION ANALYSIS OF CULTURAL HERITAGE OBJECTS USING PORTABLE X-RAY FLUORESCENCE SPECTROMETRY

X-ray emission techniques play important role in the cultural heritage area. They provide information about chemical composition of an object upon bombardment of its surface with electrons, ions, or electromagnetic radiation. Their useful features include non-destructiveness, multielemental capability, and high sensitivity for inorganic components. Especially widely used is the X-ray fluorescence technique. It utilizes electromagnetic radiation generated by X-ray tubes or radioisotope sources. X-ray fluorescence equipment is relatively simple as compared to the charged particle-based spectrometers which are combined with scanning electron microscope or ion beam accelerator. X-ray fluorescence technique can be easily adapted for in situ measurements. A portable X-ray fluorescence spectrometer has been constructed utilizing commercially available, ready made components. The construction details of the spectrometer and examples of its application are given. The key features of the portable system are the use of polycapillary X-ray optics and a vacuum chamber attachment to enhance detection of low atomic number elements such as Mg, Al, Si, P, S, and Cl. The spectrometer was applied for chemical composition analysis of archaeological artifacts and works of arts from the collections of the Museum of Fine Arts (Kunsthistorisches Museum), Vienna, Austria. The investigated objects included ancient bronzes, coins, samples of pigments, and famous goldsmith work "Saliera" by Benvenuto Cellini (1500-1571). This work highlights also other projects related to the applications of nuclear analytical techniques in support of study and preservation of cultural heritage objects supported by the International Atomic Energy Agency and carried out in the Agency's Member States.