## 3 Results and Discussion
### Laboratory EPMA-EDS Results  
EPMA-EDS analyses were performed on all micro-fragments (Table 1) investigating the superficial pictorial film. Table 3 provides a summary of the data, where the main elemental composition of paint layers is given for each sample. Although EDS analyses have a semi-quantitative nature, they can provide information about pigments by the identification of the key chemical element responsible for the color. Moreover, due to the surface alteration and to detached and damaged portions of the pictorial film, in some samples the contribution of the composition of the underlying layers \begin{table}
\begin{tabular}{c c} \hline \hline
**Analyzed Point** & **EDS Data** \\ \hline S1 & Hg, S, Pb, Fe, Ca, Si, Al, K \\ S2 & Hg, S, Pb, Fe, Ca, Si, Al, K, Ti \\ S3 & Pb, Fe, Ca, Si, Al, Mg, K \\ S4 & Si, Al, Fe, Cl, Mg, K, Na, Pb, Ca \\ S5 & Si, Al, Hg, K, Na, Pb, Ca \\ S6 & Pb, Fe, Ca, Si, Al, K, Na \\ S7 & Pb, Fe, Ca, Si, Al, K, Na \\ S8 & Si, Al, Fe, Cl, Mg, K, Na, Pb, Ca \\ S9 & Si, Al, Fe, Ca, Mg, K, Na, Ba, Pb, Ca \\ S10 & Pb, Fe, Ca, Si, Al, Mg, K \\ S11 & Si, Al, Mg, Na, Fe, K, S, Cl, Pb, Ca \\ S12 & Pb, Ca, Si, Al, Mg, Na, Fe, K, S, Ti \\ S13 & Pb, Sb, Si, Ca, Na, K, Al, Mg, S, Fe, Cl \\ S14 & Pb, Ca, Si, Al, Mg, Na, Fe, K, S, Ti \\ S15 & Si, Co, K, Ca, S, Fe, Al, K, Ti, Pb, Ca \\ S16 & Si, Al, Mg, Na, Fe, K, S, Cl, Pb, Ca \\ S17 & Pb, Ca, Si, Al, Mg, Na, Fe, K, S, Ti \\ S18 & Pb, Ca, Si, Al, Mg, Na, Fe, K, S, Ti \\ S19 & Pb, Fe, Ca, Si, Al, Mg, K, Ti \\ S20 & Pb, Ca, Si, Al, Mg, Fe, Mn, P, Na, K, Ti \\ S21 & Si, Al, Fe, Cu, K, Mg, Fe, Na, Pb, Ca \\ S22 & Pb, Fe, Ca, Si, Al, Mg, K, Na \\ S23 & Pb, Ca, Si, Al, Mg, K, Fe, S, Na, Hg \\ S24 & Pb, Hg, Sb, Ca, Si, Na, Al, Mg, K, Cl \\ S25 & Pb, Fe, Ca, Si, Al, Mg, K \\ S26 & Pb, Sb, Si, Ca, Na, K, Al, Mg, S, Fe, Cl, Ti \\ S27 & Pb, Sb, Si, Ca, Na, K, Al, Mg, S, Fe, Cl, Ti \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Energy-dispersive spectroscopy (EDS) chemical data detected on painted surfaces. was evident during the investigations. In particular, considerable contents of Pb, Ca and iron oxide with aluminosilicates were detected in all the examined samples, most likely attributable to the composition of the preparatory layers. In particular, the significant Ca and Pb content suggest that the preparatory layer could contain species linked to these compounds, such as calcium carbonate and white lead. These data are in agreement with the results coming from other studies carried out on [PERSON]'s masterpieces which report the use of such compounds for the preparatory layers especially during the Maltese period of the artist [6,8,12,13,14]. As for the two reddish samples (S1, S2), high amounts of S and Hg were both detected, leaving the hypothesis that the artist used a red mercury sulfide (HgS, vermilion) for the reddish shades. The further addition of earths is not to be excluded given the presence of Al, Ca, K, Si, and Fe which are chemical elements originating from accessory minerals, typical of the natural earth pigments from iron oxide deposits. Samples with orange-salmon tones (S3, S7), and samples with pink shades typically used to make skin colors (S6, S10, S19, S22, S23, S25) show high concentrations of Pb followed by lower quantities of Ca and further chemical elements from earths (Si, Al, Mg, K, Fe, Na, Ti). In Figure 4 some representative EPMA images collected on sample S2 and S10, along with relative EDX spectra, are reported as examples. As for the high Pb content, in addition to its use in the preparatory layer, as mentioned above, it could also be associated to the use of a mixture of Pb-based pigments having a  
Figure 4: Representative electron probe microanalyses (EPMA) images showing: (**a**) the pictorial film (sample S2, scale bar 100 \(\upmu\)m) and (**b**) the layers below the pictorial film (sample S10, scale bar 100 \(\upmu\)m) along with relative EDS spectra.