## 4 Results  
The obtained minero-petrographic, chemical, and micro-chemical data are described by listing them according to the different architectonic locations, i.e., niche, recumbent figure, and pediment, respectively. The niche rock substrate (Figure 3a) is covered by two finishing layers: the outer thin white preparation is overlapping a layer of plaster in contact with the tuff. Occasionally, the plaster does not show good adhesion, and is mostly detached from the surface of the rock. The microscopic observations, under the polarized light microscope (PLM), highlight the first preparation layer onto which the color was applied, constituted by a Ca lime layer (the thickness is approximately between 100 \(\upmu\)m and >1.0 mm). The lime contains sporadic tuff inclusions (600-800 \(\upmu\)m in size), a medium-low porosity, and some fractures. Below the first layer, a mortar (thickness >2 mm), realized with an air-hardening calcite lime binder of anisotropic aspect and micritic texture, is present; the aggregate, dispersed in the binder, is well-sorted with subrounded shape. The binder/aggregate ratio is approximately 2/3. The carbonate binder, which includes numerous lumps (400-900 \(\upmu\)m in diameter), displays a porosity consisting of irregular voids with dimensions rarely greater than 400 \(\upmu\)m. The main components of the aggregate are represented by rounded crystals of sanidine (0.3-1.1 mm), pyroxenes (400-600 \(\upmu\)m), and rounded fragments of siltstone (400-900 \(\upmu\)m), in addition to tuff, and metamorphic and sandstone fragments (Figure 4a). The finishing of the sculpted parts inside the niche (recumbent figure and _kline_) (Figure 3b) is constituted by two preparatory layers. The outer one is of white color (variable thickness between 30 and 150 \(\upmu\)m) and had the function to make possible the painting; the layer applied below (thickness between 350 \(\upmu\)m and 2 mm) had a double function, which was to smooth the rock surface and to enable to model different parts of the sculpture. Both of them are constituted by a Ca lime layer similar to that used in the  
Figure 4: Crossed polarized light images of (**a**) the niche, a thin white Ca lime layer overlapping the plaster where feldspars, pyroxenes, and iron oxides are visible; (**b**) the recumbent figure, two finishing Ca lime layers are shown; (**c**) detail of the pediment where a thin white preparatory layer with isotropic aspect overlaps the tuff rock substrate. outer layer of the niche. The lime layers have a porosity of small dimensions (<0.4 mm), (mostly due to drying-out fractures), numerous lumps, and tuff fragments (rare, apart from where they are in contact with the substrate) (Figure 4b). The preparatory layer to the color used for the decorations of the sculptured surfaces outside the niche (pediment and winged figure) is significantly different from those previously described (Figure 3c). This layer is white but translucent, and has a reduced thickness (30-300 um) with respect to those of the niche. It appears compact and isotropic, without any inclusion (Figure 4c). The mineralogical data (Table 2) obtained by X-ray diffractometry, confirm the petrographic observations on the three architectonic locations. The outer layers of the niche show a calcite composition constituting the Ca lime layer, while in the plasters are mainly present calcite, quartz, feldspar, pyroxene and, in trace quantities, phyllosilicate and zeolite. Inside the niche, over the recumbent figure and _kline_, the outer lime layer shows a composition with calcite and traces of pyroxene and zeolite. In the underlying lime layer, in contact with the rock, only calcite is present. In the pediment, the XRD data show zeolite (chabazite) and k-feldspar (sandine), in addition to traces of calcite, quartz, and gypsum (Figure 5). The results of the chemical analysis (ATR-FTIR) (Table 3) confirm the mineralogical data.