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In this work, a study of detection systems in portable X-ray fluorescence (PXRF) spectrometry was performed. An assessment of various detectors and their influence on the measurement of trace elements in different bulk materials, from light to heavy matrices, was done. Four reference materials were analyzed: Orchard Leaves (NBS-1571); Bone Meal (NIST-1486); River Sediment (NBS-1645) and Free-Cutting Brass (NBS-1105). Detection limits were calculated for the elements present in the reference materials, quantitative calculations were performed for three known samples and a comparison was made for each detector. Three case studies were also performed in order to appraise the behavior of the detection systems: A paper document from 1909, a potassium alum/calcite mixture and a Portuguese coin.

Two pairs of hand-painted Japanese folding screens were analyzed by Raman, energy dispersive X-ray fluorescence (EDXRF) and Fourier transform infrared (FTIR) spectroscopy, in order to characterize the materials used in their production. Japanese folding screens, called byobu, are one of the oldest and most highly refined forms of Japanese art, where paper and silk were used as materials for the artists to paint on. The two pairs of folding screens studied in this work also exhibit a golden background to create a luminous effect. These screens depict some of the Portuguese who arrived to Japan during the 16th century, initiating active commercial and cultural exchange between Japan and the West, called the Nanban Trade. Nowadays, only about 60 examples of this Namban genre remain, so the study of these two pairs is of utmost importance to the knowledge of this precious craft. The materials identified, such as gold, silver, malachite, azurite, vermillion, red lead, red madder, yellow ochre, white oyster shell, and carbon black, are part of the traditional Japanese palette.

A complete multianalytical study of a hand-coloured map from the seventeenth century is presented. The pigments atacamite, massicot, minium, gypsum, carbon black and vermilion were determined by means of XRF and Raman spectroscopy. The state of conservation of the cellulosic support was monitored by means of unilateral NMR. The analysis was nondestructive and noninvasive, and thus several spectra were collected from the same areas, yielding more reliable results without damaging the artwork. The role of copper pigments in the oxidation processes observed in the cellulosic support is discussed, as well as the possible provenance of atacamite as a raw material instead of as a degradation product of malachite.

Synchrotron radiation X-ray fluorescence spectroscopy, in conjunction with atomic absorption and Raman spectroscopy, was used to analyze a set of top brand tattoo inks to investigate the presence of toxic elements and hazardous substances. The Cr, Cu, and Pb contents were found to be above the maximum allowed levels established by the Council of Europe through the resolution ResAP(2008)1 on requirements and criteria for the safety of tattoos and permanent makeup. Raman analysis has revealed the presence of a set of prohibited substances mentioned in ResAP(2008)1, among which are the pigments Blue 15, Green 7, and Violet 23. Other pigments that were identified in white, black, red, and yellow inks are the Pigment White 6, Carbon Black, Pigment Red 8, and a diazo yellow, respectively. The present results show the importance of regulating tattoo ink composition.