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Table 1 Summary of characteristic signatures from FTIR spectroscopy, SEM-EDX, SQWV and XRD for the minerals identified in samples 1 and 2 of funerary pigments found in the Rio Azul tomb

From: Funerary colors in Pre-classical Maya culture: the red pigment in the 19th tomb of Rio Azul (Peten, Guatemala)

Mineral
(Ideal Chemistry)
SEM-EDX
Main emission lines identified
VMP
Main Cathodic and anodic peaks
(mV)
FTIR spectroscopy
Wave numbers
(cm−1)
XRD
d-spacing
(Å)
Calcite
CaCO3
Calcium: Kα (Ca), Kβ (Ca) 1394, 870, 710 3.033, 2.285, 2.095, 1.913
Gaylussite
Na2Ca (CO3)2
Calcium: Kα (Ca), Kβ (Ca)
Sodium: Kα (Na)
1403, 870, 710
Cinnabar
HgS
Sulphur: Kα (S)
Mercury: Mα (Hg), LαHg), Lβ (Hg)
Cathodic peak: +30; Anodic peak: − 450 3.359, 2.865, 2.027, 1.980,
Galena
PbS
Sulphur: Kα (S)
Lead: Mα (Pb), Lα (Pb), Lβ (Pb)
– 
Goethite
FeO (OH)
Iron: Kα (Fe), Kβ (Fe) Cathodic peaks: +150 and − 200
Haematite
Fe2O3
Iron: Kα (Fe), Kβ (Fe) Cathodic peak: − 400 570, 550 2.702, 2.519, 1.842, 1.696
Halloysite/kaolinite
Al2Si2O5 (OH)4
Aluminum: Kα (Al)
Silicon: Kα (Si)
3693, 3671, 3653, 3623, 3410, 1640, 1163, 1113, 1029, 1006, 937, 910, 795, 779, 753, 687, 533 Halloysite: 7.522, 4.451, 3.633, 2.568
Kaolinite: 7.179, 3.576, 2.341, 1.486
Hydroxylapatite
Ca5 (PO4)3 (OH)
Phosphor: Kα (P)
Calcium: Kα (Ca), Kβ (Ca)
1021, 638, 593
Quartz
SiO2
Silicon: Kα (Si), Kβ (Si) 1163, 1150, 1085, 798, 780, 695, 514 4.259, 3.343, 1.817, 1.541
Whewellite
Ca2C2O4∙H2O
1617, 1315, 779