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Zeolites are present in numerous outcrops of volcanites of different ages in Sicily (Italy). Some of these outcrops are important because they constitute the ideal genesis conditions of some of these minerals, which represent geological indicators of chemical and geothermal gradients involved during their formation. For this purpose, a group of zeolites coming from areas of the Ionian coast and Palagonia village (Eastern Sicily) was investigated by means of Raman spectroscopy. In the geological record, these areas have been influenced by intense volcanic events that produced mineralization of hydrothermal origin. Sicilian zeolite samples were analysed in situ using different mobile Raman apparatus, directly on the outcrops of Aci Castello and the nearby Lachea Island, or in local collections where they are preserved. Some of these samples have been then analysed using laboratory micro-Raman to compare the results and identify the zeolite types. The strength and weakness points of each instrument have been highlighted. Often, the Raman spectra of zeolites are affected by broad fluorescence, making them of difficult interpretation. However, satisfying results were obtained with portable devices, whose identifications were confirmed by micro-Raman, discerning zeolites of different groups, such as analcime, chabazite, natrolite and phillipsite. The use of portable instruments has demonstrated the possibility to obtain identification of zeolites and related minerals both on site and in the laboratory, whose results match with the geological setting of the considered areas.

In archaeometry, the advantages of a combined use of Raman spectroscopy and X-ray fluorescence spectroscopy are extensively discussed for applications such as the analysis of paintings, manuscripts, pottery, etc. Here, we demonstrate for the first time the advantage of using both techniques for analysing glyptics. These engraved gemstones or glass materials were originally used as stamps, to identify the owner, for instance on letters, but also on wine vessels. For this research, a set of 64 glyptics (42 Roman glass specimens and 22 modern ones), belonging to the collection of the museum 'Quinta das Cruzes' in Funchal (Madeira, Portugal), was analysed with portable Raman spectroscopy and handheld X-ray fluorescence (hXRF). These techniques were also used to confirm the gemological identification of these precious objects and can give extra information about the glass composition. Raman spectroscopy identifies the molecular composition as well as on the crystalline phases present. On the other hand, hXRF results show that the antique Roman glass samples are characterised with low Pb and Sn levels and that the modern specimens can be discriminated in two groups: lead-based and non-lead-based ones.

Tomato (Solanum lycopersicum) fruit samples, in two ripening stages, ripe (red) and unripe (green), collected from a cultivar in the North of Spain (Barrika, Basque Country), were analyzed directly, without any sample pretreatment, with two different Raman instruments (portable spectrometer coupled to a micro-videocamera and a confocal Raman microscope), using two different laser excitation wavelengths (514 and 785 nm, only for the confocal microscope). The combined use of these laser excitation wavelengths allows obtaining, in a short period of time, the maximum spectral information about the main organic compounds present in this fruit. The major identified components of unripe tomatoes were cutin and cuticular waxes. On the other hand, the main components on ripe tomatoes were carotenes, polyphenoles and polysaccharides. Among the carotenes, it was possible to distinguish the presence of lycopene from b-carotene with the help of both excitation wavelengths, but specially using the 514 nm one, which revealed specific overtones and combination tones of this type of carotene. This work has been financially supported by Research Project S-PE11-UN128 of the Basque Country government. Technical and support provided by SGIker (UPV/EHU, MICINN, GV/EJ, ESF) is gratefully acknowledged.