## 4 Discussion  
### Age Results Discussion  
The available data on the equivalent dose conclusively affirm that SE9, a granitoid substrate rock unaffected by pyrometamorphism, has retained its original characteristics over time, placing it firmly within a distinct geological era. Used as a benchmark, SE9 sample provided a means to evaluate the effectiveness of the method.  
Remarkably, sample SE6 also behaves like sample SE9. It therefore appears to have retained its geological age. SE6 corresponds to a granitoid rock fragment collected at the top of the vitrified structure and showing macroscopic indications of pyrometamorphism. This fact is difficult to explain. According to the analyses of [PERSON] et. al., its mineralogy is rather peculiar [12]. Noteworthy is the uncommon presence of traces of the high-pressure cohesive phase together with cristobalite, combined with the absence of other heating indicators. A possible explanation for this inconsistency is that the mineralogy of this rock fragment located at the surface of the vitrified structure was influenced not only by the heating event due to wood combustion, but also by a shock metamorphic event correlated to lighting strikes. For clarity of the image range, the results of SE9 and SE6 are not shown graphically in Figure 6.  
The TL dating of all analyzed samples shows a wide range of age values (1740 BCE to 550 CE). The glass cements, consisting mainly of amorphous components (glass), are significantly younger than rock fragments that have undergone only a small partial melting.  
Theoretically, the large dispersion of calculated ages could be related to distinct episodes of heating and vitrification that occurred over time. However, a solid set of evidence seems to dismiss this possibility. It has been seen that the pyrometamorphism that affected the upper portion of the structure led to the formation of a single (up to 90 cm) and compact vitrified crust. Within this crust, there are no facies variations traditionally associated with weathering or indicative of discontinuous and repetitive heating events, so  
Figure 6: Final date ranges in correspondence to the Bronze and Iron Ages in southern Italy. In orange are samples belonging to the category of heated or partially vitrified rocks. In light blue are the vitreous cements.  
that it appears justified to assume that the vitrification of the structure was achieved as a result of a single episode that occurred within a given time interval.  
The significant age differences measured in the glass cements characterized by very low crystallinity compared to the pyrometamorphite samples affected by relatively low partial melting suggest that these age discrepancies can be attributed to intrinsic limitations of the measurement protocol.  
These limitations appear to be closely related to the dosimetric properties of quartz in the glassy matrix, a topic extensively discussed in the 2019 paper by [PERSON] et al. [27].  
A parallel investigation is underway to assess the potential impact of self-absorption in the light signal, possibly influenced by the dark color of the vitreous cements, which were found to be younger than the granitoid pyrometamorphites (Table 6).  
In this context, it is worth noting that the iron (Fe) content in vitreous cement samples, especially those of recent origin, can be remarkably high (up to 26.24% Fe\({}_{2}\)O\({}_{3}\), as reported by [PERSON] (University of Modena and Reggio Emilia), personal communication, in sharp contrast to the Fe content observed in rock fragment samples with granitoid composition.  
In the framework of a unique pyrometamorphic event responsible the vitrification of the structure, the current focus is on determining the most likely age of this conversion.  
Therefore, excluding the data on vitreous cement and the data on the anomalous age of the SE 7 sample (Table 6), it is reasonable to conclude that the vitrification of the Serravuda structure took place between 1010 and 470 BCE, i.e., during the Late Bronze Age and Early Iron Age.