Raman and laser‐induced breakdown spectroscopy (LIBS) spectroscopies will play an important role in planetary exploration missions in the following years, not only with Raman instruments like Raman laser spectrometer on board of Rosalid Franklin Rover or scanning habitable environments with Raman and luminescence for organics and chemicals on board Mars2020 Rover but also with combined instruments such as SuperCam. These techniques will be part of the upcoming planetary exploration missions because they can provide complementary information from the analysed sample while potentially sharing hardware components, maximizing the scientific return of the samples while limiting mass. In this framework, this study seeks to test the feasibility of combining several univariate and multivariate analysis techniques with data fusion techniques of different instruments (532 and 785 nm Raman and LIBS) to evaluate the improvements in the quantitative classification of samples in binary mixtures. We prepared two‐component mixtures that are potentially relevant in planetary exploration missions, using two different sulfates and a chloride. A more accurate classification of the samples is possible through a univariate analysis that combines the calculated concentration indicators for Raman and LIBS. On the other hand, multivariate analysis was run on Raman, LIBS, and Raman + LIBS low‐level fused data sets. The results showed a better improvement when fusing LIBS and Raman when compared with the redundant fusion but not a systematic improvement when compared with individual sets. We demonstrate that a quantification of the mineral abundances in binary mixtures can be obtained from Raman and LIBS data using univariate and multivariate analysis techniques, being the latter remarkably better, moving from performances of classification, in the whole range of concentrations, that could be over the 10% to values under 3.5%. Furthermore, the fusion of data coming from these techniques improves the classification limit with respect to the individual techniques. Thus, besides the (evident) hardware convenience of combining LIBS with 532‐nm Raman, there could be analytical advantages as well.

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A set of chromolithographs from the 19th century were analysed to identify the fillers and pigments used for their elaboration. Because of the delicacy of the chromolithographs, the research involved the use of Raman, Fourier‐transform infrared and energy dispersive X‐ray fluorescence spectroscopies for a complete characterization of the works on paper without removing any microsamples. Despite the high fluorescence of the samples when analyzed by Raman spectroscopy, in this paper, we demonstrated that ink spectra can be successfully enhanced by subtracting the spectra of the supporting background paper. The results of the study showed that, apparently, the lithographer used a limited range of common inorganic pigments from the 19th century (carbon black, chrome yellow, Prussian blue, red ochre, red lead and vermilion) together with organic pigments (indigo blue, gamboge and a red organic pigment). The study also found that despite the fact that during the 19th and early 20th century the use of mixtures of several pigments was a common practice, unusual admixtures were used for the preparation of some colours of the studied chromolithographs. Copyright © 2011 John Wiley & Sons, Ltd.

11Energy dispersive X-ray fluorescence is a common analytical tool for layer thickness measurements in 12 quality control processes in coating industry, but there are scarce microanalytical applications in order to artworks. The method was tested on standard reference materials: dried droplets of monoelemental 19 standard solutions laid on a metallic plate of copper. As an example of application, we estimated pigment 20 mass distribution of two "oil on copper" painting from the sixteenth and eighteenth century respectively. 21Pictorial layers have been complementarily analyzed by X-ray diffraction. 22Apart of the supporting media made of copper or brass, we could identify two different superimposed 23 layers: a) a preparation layer mainly composed by white lead and b) the pictorial layer of variable 24 composition depending on the pigments used by the artist on small areas of the painting surface. The areal 25 mass distribution of the different elements identified in the painting pigments (Ca, Cr, Mn, Fe, Zn, Cd, 26 Hg and Pb) have been determined by elemental mapping of some parts of the artworks.