## 3 Results
### Results of X-Ray Investigations Obtained for the Sampled Mortars
Microstructural Characteristics of Mortars Investigated by Scanning Electron Microscopy (SEM) Coupled with Energy Dispersive Spectroscopy (EDX)  
The micro-structural characteristics of the investigated mortars were determined through scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDX). Scanning electron microscopy (SEM) was used to visualize the morphology and textural relationships of the various mineral phases identified via XRD. Supplementing the information provided by electron microscopy techniques with data obtained through complementary XRD methods offers an advantage in the comprehensive morphological and structural characterization of binder matrices [37]. Figure 10 presents the images obtained through scanning electron microscopy (SEM) for the collected mortar samples. The images in Figure 10 highlight the presence of a mixture of phases with specific morphologies based on calcium carbonate. These results, obtained via scanning electron microscopy (SEM), were consistent with the information found in the specialized literature and with the X-ray diffraction results, which indicated the presence of carbonate matrices typical of such mortars [38]. Scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDX) also allowed for the determination of the elemental composition of the collected samples. Figure 11 presents the results obtained through energy-dispersive X-ray spectroscopy (EDX) for the investigated mortars. The EDX spectra recorded on the collected mortar samples provided information about the chemical elements present in each sample. In all the investigated samples, specific peaks corresponding to the elements of interest--Ca, Si, Al, and O--were observed, along with small amounts of Na, K, Fe, and Mg, as well as differences in intensity, as shown in Table 4. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**No.** & **Mineral Phases** & **Structure Type** & **Spatial** & **XRD Intensity** \\  & & & **Group** & **(I/I\({}_{0}\))** \\ \hline
1 & Calcite (CaCO\({}_{3}\)) & & & 3.035 & \\  & & & & 2.095 \\  & & & & 2.285 \\ \hline
2 & Aragonite (CaCO\({}_{3}\)) & & & 3.396 & \\  & & & & 1.977 & \\  & & & & 3.273 & \\ \hline
3 & Quartz (SiO\({}_{2}\)) & & & 3.34 & \\  & & & & 1.81 & \\ \hline
4 & Brammallite & & & 1.485 & \\  & (Na,H\({}_{3}\)O)(Al,Mg,Fe)\({}_{2}\)(Si,Al)\({}_{4}\)O\({}_{10}\) & & & C2/c & 9.77 \\  & & [(OH)\({}_{2}\),(H\({}_{2}\)O)] & & & 3.17 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Mineral phases identified by X-ray diffraction. Figure 10: Scanning electron microscopy (SEM) images for: (**a**,**b**) Sample 1; (**c**,**d**) Sample 2a; (**e**,**f**) Sample 2b; (**g**,**h**) Sample 3; (**i**,**j**) Sample 4. The concentration of these elements in the investigated mortar samples (Figure 12) showed variations in intensity, which could be attributed to local inhomogeneities. The highest proportion in the analyzed samples was calcium, due to the presence of calcium carbonate, followed by silicon, due to the presence of quartz. These results were fully consistent with those obtained through X-ray diffraction, except for Sample 1, where a lower proportion of calcium and a higher proportion of silicon were observed. Figure 11: EDX analysis images for: (**a**) Sample 1; (**b**) Sample 2a; (**c**) Sample 2b; (**d**) Sample 3; (**e**) Sample 4. Figure 12: The content of principal elements in investigated mortar samples.