## 3 Results and Discussion
### SEM-EDS Analysis
#### 3.3.1 Iron Samples  
Sample 1. Three different macro-areas are selected to be analyzed using SEM-EDS. In each macro-area, a few smaller areas are investigated (Figure 5). SEM-EDS analyses show a homogeneous morphology of sample 1, with the presence of fractures and inclusions. The chemical composition of this sample reveals a high Fe\({}_{2}\)O\({}_{3}\) content, ranging from 93.49 and 81.54 (Table 2). ZnO, CaO and P\({}_{2}\)O\({}_{5}\) are also present in minor quantities with variable oxide concentrations in all analyses. SiO\({}_{2}\), Al\({}_{2}\)O\({}_{3}\), Na\({}_{2}\)O, MgO and SO\({}_{2}\) are present in low concentrations. Regarding K\({}_{2}\)O, Cl, CuO and SO\({}_{2}\) the concentrations are close to the detection limit of the instrument, Pb and Sn are not detected. Sample 5. This sample is characterized by two large areas, i.e., the surface that seems unaltered and the excavated area containing some spherules (Figure 6). The sample has a porous morphology. The content of Fe\({}_{2}\)O\({}_{3}\) varies from 87.54 to 90.94 (Table 2). Low concentrations of SiO\({}_{2}\), Al\({}_{2}\)O\({}_{3}\), Na\({}_{2}\)O and MgO are observed as suggested by the intensity of their peaks resulting in a similar composition to that of sample 1. In addition, P\({}_{2}\)O\({}_{5}\) is present in all the analyses with a maximum value of 4.02, CaO with a value close to 1. The metals ZnO and CuO were present, as well as CaO. Sulphur and Cl have concentrations close to the detection limit of the instrument. Pb and Sn are not detected. \begin{table}
\begin{tabular}{c c c c c c c c c c c c c c} \hline \hline
**Bronze** & **SiO\({}_{2}\)** & **Al\({}_{2}\)O\({}_{3}\)** & **Fe\({}_{2}\)O\({}_{3}\)** & **MgO** & **CaO** & **Na\({}_{2}\)O** & **K\({}_{2}\)O** & **SO\({}_{2}\)** & **CI** & **CuO** & **SnO** & **PbO** & **P\({}_{2}\)O\({}_{5}\)** & **Tot** \\ \hline \multirow{9}{*}{**S**-**} & 0.57 & 3.60 & 1.48 & 0.22 & 0.40 & n.d. & n.d. & n.d. & 0.51 & 89.63 & 3.12 & 0.47 & n.d. & 100 \\  & 0.31 & 2.21 & 0.93 & n.d. & n.d. & n.d. & n.d. & 0.28 & 94.53 & 1.73 & n  
In the samples incorporated into the resin and sectioned (samples 8, 10 and 32), different spectra were analyzed for each area selected, but the paper showed only the  
Figure 5: Schematic of the areas investigated by SEM-EDS for sample 1. Areas 61 and 63 (colored in yellow) were characterized by a large dark spot with fractures. The central area 65 and 67 (colored in white) appeared more homogeneous in a brown color. Colored in red, there was a black part that seem thinner (detail 73), while the rest of the surface had an intermediate color between black and brown (area 71). SEM images are related to detail 63 (in yellow), detail 67 (in white), detail 73 (in red). Figure 6: Schematic of the areas investigated by SEM-EDS for sample 5. The spherules are shown in area 53 and two details 55 and 57, colored white. Area 59, colored in yellow, had a homogeneous appearance. SEM images are related to detail 55 and 57.  
representative spectra for each analyzed area. All the samples were not characterized by metal elements such as Cu, Zn, Sn and Pb. Sample 8 was characterized by a high value of Fe oxide in all the parts of the sample analyses, as shown in the spectra of Figure 7 and in Table 2. Aluminum, Si, P, Cl, K and Ca oxides were observed but with very low values. Na, Mg, S and the metals Cu, Zn, Sn and Pb oxides were not detected or were very close to the detection limit of the instrument. Sample 10. Figure 8 showed SEM images of the analyzed areas; the sample appeared with a homogenous morphology with small fractures. The chemical composition reported a high value of Fe\({}_{2}\)O\({}_{3}\), close to sample 8, especially in the first three EDS-spectra that ranged from 96.49 to 98.02 (Figure 8a,b and Table 2). Only the spectrum of Figure 8c showed a lower value of Fe with respect to the other spectra (87.49) and a very low amount of Cu  
Figure 7: SEM images and EDS spectra of the sample 8: (**a–c**) detailed spectra for each area selected. and Zn oxides.