## 3 Results
### Minimally Invasive Analysis of Pigments
#### 3.2.2 Red Pigments  
The presence of cinnabar as deduced from non-invasive XRF analysis was confirmed by Raman (252, 282, and 343 cm\({}^{-1}\)), \(\upmu\)XRD, and SEM-EDS analyses of a few pigment particles collected from a flight feather (sample 2R). Bright red particles of pigment, consistent with this interpretation, were imaged in these locations by digital microscopy, surrounded by darker particles of weathered cinnabar, most likely metacinnabar. The presence of cinnabar was detected in the youth's arbyallos and the sphinx's chest, wing, diadem, necklace, and eyes. No traces of gypsum were detected by Raman, \(\upmu\)XRD, or SEM-EDS, suggesting that cinnabar was not mixed in with gypsum. \begin{table}
\begin{tabular}{c c c c} \hline
**Sample** & **Description** & **Color** & **Location** \\ \hline S1B & Loose particle & Blue & End of the tail \\ S2R & Loose particles & Red & Flight feather of the proper right wing \\ S3R & Loose particles & Brown/Red & Lioness skin, between wings \\ S4R & Cross section & Red & Sphinx’s hair \\ S5R & Loose particles & Brown/Red & Front left leg \\ S6Y & Loose particles & Yellow & Back of the diadem \\ S7 Bl & Loose particles & Black & Flight feather outline of the proper right wing \\ S8 Bl & Loose particles & Black & Genitals of the sphinx \\ S9W & Loose particles & White & Left eye of the sphinx \\ S10R & Cross section & Red & Sphinx’s hair \\ \hline \end{tabular}
\end{table} 
Table 1: List of micro-samples removed from the sphinx, with corresponding description and sampling locations. Two cross sections from the sphinx's hair (samples S4R and S10R), where Fe-containing pigments were identified by non-invasive XRF, show a complete stratigraphy that included the marble substrate, a red pigment layer, and a thick accretion. The stratigraphy indicated that the pigment was applied directly to the marble surface without a preparation layer, confirming the observations collected by digital microscopy (Figure 9). The pigment layer consisted of clusters of very fine Fe-oxide platelets not exceeding 1 \(\upmu\)m in size, associated with very fine silicates, most likely clay minerals, rare quartz, and very rare pyrite, suggesting that this red pigment was a highly refined red ochre. The presence of hematite was identified by Raman spectroscopy and \(\upmu\)XRD. It is worth noticing that traces of arsenic (As) were detected in hematite particles (up to 1 wt%) by EDS analysis, an occurrence reported in red lumps of pigments excavated from the pigment workshop of the Koan agora, Kos, Greece [38]. Scattered clusters of platy Fe-oxide/hydroxide particles, most likely hematite, containing traces of As, and fine-grained silicates, were also identified in a loose sample collected from the lioness skin between the wings (sample 3R, Figure 10), suggesting that red ochre was used for the decoration of this portion of the sphinx's body. Given the nature of the sample, it was not possible to determine if red ochre was used in purity or mixed in with other pigments. Figure 8: BSE image of sample 1B showing particles shapes and grainsize (**bottom**); PLM image of sample 1B (**top left**) and Raman spectrum measured on one of the blue particles (**top right**). Figure 10: BSE images of sample 3R with corresponding EDS spectrum (**left**), and of a typical platy Fe-oxide/hydroxide particle (**right**). Figure 9: BSE image of cross section 4R (**bottom**) showing the paint stratigraphy of the hair (1. Marble substrate; 2. Paint layer; 3. Accretion); EDS spectrum (**top left**) of a sporadic cinnabar particle in the paint layer (very bright particle at the center of layer 2); Raman spectrum of the hematite particle indicated in the figure (**top right**). A few particles of cinnabar were detected in cross section S4R from the sphinx's hair (Figure 9) and from a loose sample collected from the front left leg (sample 5R).