# Synchrotron X-ray Microprobes: An Application on Ancient Ceramics
## 2 Materials and Methods  
In this case, 14 samples of black-gloss ceramics from the excavations of the Greek colonies of Gela and Messina (Sicily, Italy) have been selected for this study. They are representative of two different productions, Laconian (GEL 1-8) and so-called Chalcidian (ME 67-70, 73, 133). The classification was preliminarily based on the morphological and typological features of the selected specimens and on macroscopic observations of the black-gloss and the paste (Table 2). Attic products and Sicilian (Geloa) and south-Italian (Locrian?) colonial products already characterized in a previous research [22] were also re-considered for the purpose of comparison. The so-called Chalcidian pottery is known in literature for both figurative and anionic series, dated from the 6 th century B.C. to the beginning of the 5 th century B.C. According to the most recent archaeological studies, it is a colonial product that has been located in the southern Calabria or in the Strait of Messina area [34-37]. Laconian black pottery is produced in the Greek region of Laconia during the 6 th century B.C. and is exported to different sites in the Mediterranean [38,39]. For the experiments, small fragments were sampled from vessels preserved in Archeological Museums of Gela and at the deposits of the Superintendence of Messina. Vessels from Messina classified as Chalcidian were also studied by benchtop XRF and ICP-MS in the frame of previous published research, pointing out some geochemical criteria for productions discrimination, which are based--however--on destructive methods [35]. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \begin{tabular}{c} Life Sciences, Materials \\ sciences, CH \\ \end{tabular}  \\
26-ID & APS & USA & 6-12 & \ \begin{tabular}{c} \(\mu\)XRF, \(\mu\)XRD \\ \end{tabular}  & 0.03 \(\times\) 0.03 & Air & \begin{tabular}{c} Life Sciences, Materials \\ sciences, CH \\ \end{tabular}  \\
20-BM-B & APS & USA & 2.7–32.7 & \begin{tabular}{c} \(\mu\)XRF, \(\mu\)XANES \\ \end{tabular}  & \ \begin{tabular}{c} \(5\times 5\) or 25 \\ \(2\times 2\) \\ \end{tabular}  & Air & \begin{tabular}{c} Life Sciences, Materials \\ sciences, CH \\ \end{tabular}  \\  
Non-destructive and non-invasive preliminary studies [22] at micro-samples on Attic, Sicilian and South-Italian colonial products pointed out enrichment-depletion of specific elements in clay paste and black gloss useful as provenance indicators. Additionally, Zn has been verified as peculiar of non-Sicilian colonial products and of specific manufacturing practices [22], of which nature and workshop distribution needs to be verified. The analysis of the selected corpus by different non-destructive and non-invasive methods offered the opportunity to explore the challenges offered by the combination of SR based \(\upmu\)XRF and \(\upmu\)XANES mapping in providing valuable provenance and technical features for this ceramic class. A very preliminary qualitative chemical characterization was obtained by portable XRF mapping using an [PERSON] device equipped with an x-y motor stage and an X-ray tube with Rhodium anode. The measuring spot on the surface was about 1 mm. 2D maps were acquired on the gloss surface using a 40 kV tension of the X-ray tube, 80 \(\upmu\)A current, 3 s/point acquisition time. However, the large analysis spot (about 1 mm) prevented the necessary resolution for accurate determination of the black-gloss features; in addition, the analysis is expected to be influenced by bulk composition. Following a successful microchemical approach on black-gloss potteries [22] micro-samples were analysed at PUMA beamline, Synchrotron Soleil (France). A KB mirror focuses the X-ray photons to a spot of 3 \(\upmu\)m \(\times\) 3 \(\upmu\)m on the sample. The surface to be analyzed is orientated at an angle of 45\({}^{\circ}\) in respect to the beam axis, producing an effective beam size of 3 \(\upmu\)m in vertical and 4.3 \(\upmu\)m in horizontal direction. The measurements were performed in ambient air and temperature.