Table 1 Summary of the results of FTIR, Raman and HPLC analyses of samples taken from Terracottas A–C
Sample | Material analysed | Analytical results | ||
|---|---|---|---|---|
FTIR | Raman | HPLC | ||
Terracotta A—statuette of a woman with duck and conch shell (1846,0925.34) | ||||
A1 Purple pigment | Pink particles | Amorphous hydrated alumina (attributed to the lake substrate) | Purpurin, pseudopurpurin/munjistin (attributed to organic colorants derived from madder, likely from Rubia spp.) | |
Blue particles | Egyptian blue | |||
White particles | Kaolinite (attributed to the ground layer) | |||
A2 White pigment/ground | White particles | Kaolinite (attributed to the ground layer) | ||
A3 Blue pigment | Blue particles | Egyptian blue Quartz Calcite | Egyptian blue | |
A4 and A5 Red/orange pigment | Red and yellow particles | Red Ochre Quartz Gypsum | Hematite (red particles) Goethite (yellow particles) | |
White particles | Kaolinite (attributed to the ground layer) | |||
Terracotta B—group of two female figures sitting on a couch (1885,0316.1) | ||||
B1 White pigment/ground | White particles | Kaolinite Alunite (attributed to the ground layer) Gypsum | ||
B2 Red/orange pigment | Deep red particles | Cinnabar | ||
Red/orange particles | Iron oxide Quartz | Hematite | ||
White particles | Kaolinite Alunite (attributed to the ground layer) Gypsum | |||
B3 Blue pigment | Blue particles | Egyptian blue | Egyptian blue | |
B4 Flesh tone pigment | Red particles | Hematite | ||
White particles | Kaolinite Alunite (attributed to the ground layer) Gypsum | |||
B5 Pink pigment | Pink particles | Amorphous hydrated alumina (attributed to the lake substrate) | Purpurin, pseudopurpurin/munjistin (attributed to organic colorants derived from madder, likely from Rubia spp.) | |
White particles | Kaolinite Alunite (attributed to the ground layer) | |||
B6 Red/orange pigment | Red particles | Red ochre | Hematite | |
Yellow particles | Goethite | Goethite | ||
Black particles | Amorphous carbon | |||
White particles | Kaolinite Alunite (attributed to the ground layer) | |||
B7 Black pigment | Black particles | Amorphous carbon | ||
White particles | Quartz Kaolinite (attributed to the ground layer) | |||
Terracotta C—oinochoe in the form of a female head (1846,0925.26.a) | ||||
C1 White pigment | Blue particles | Egyptian blue | ||
White particles | Gypsum Kaolinite (attributed to the ground layer) | |||
C2 Red/brown pigment | Dark red particles | Cinnabar | ||
White particles | Calcite Gypsum Kaolinite (attributed to the ground layer) | |||
C3 Purple pigment | Pink particles | Amorphous hydrated alumina (attributed to the lake substrate) | Purpurin, pseudopurpurin/munjistin (attributed to organic colorants derived from madder, likely from Rubia spp.) Flavokermesic acid (attributed to organic colorant from an insect source) | |
Blue particles | Egyptian Blue | |||
White particles | Gypsum (attributed to the ground layer) | |||
C4 Blue pigment | Blue Particles | Egyptian Blue | ||
White particles | Gypsum (attributed to the ground layer) | |||
C5 White/ground | White particles | Calcite Gypsum Kaolinite (attributed to the ground layer) | ||
C6 Pink pigment | Deep red particles | Cinnabar | ||
White particles | Calcite Gypsum (attributed to the ground layer) | |||
C7 Dark purple (blackened red) pigment | Deep red particles | Cinnabar | ||
White particles | Calcite Gypsum Kaolinite (attributed to the ground layer) Quartz | |||