Modelling clay materials used in artworks: an infrared spectroscopic investigation

Heritage Science

Table 3 Major infrared band assignments for modelling clay samples from Hinder artworks

Wavenumber/cm⁻¹	Band assignments	References
595	Gypsum S–O bending	[19, 20]
664	Gypsum S–O stretching	[19, 20]
711	CaCO₃ C–O bending	[6,7,8,9]
728	Paraffin C–H rocking	[10, 11, 13, 14]
766	Goethite O–H bending	[21, 22]
852, 872	CaCO₃ C–O bending	[6,7,8,9]
1000–1300	Oxidation products C–O and C–C stretching	[17, 23]
1000–1300	Gypsum S–O stretching	[19, 20]
1385	Paraffin C–H bending	[10, 11, 13, 14]
1413	CaCO₃ C–O stretching	[6,7,8,9]
1456	Paraffin C–H bending	[10, 11, 13, 14]
1550–1750	Water O–H bending	[23]
	Gypsum O–H bending	[19, 20]
	Oxidation products C=O stretching	[16,17,18, 23]
1790	CaCO₃ C=O stretching	[6,7,8,9]
2522	CaCO₃ overtone/combination band	[7, 8]
2725	Aldehyde O=C–H stretching	[23]
2848, 2865, 2917, 2948	Paraffin C–H stretching	[10, 11, 13, 14]
3100–3700	Water O–H stretching	[17, 23]
	Oxidation products O–H stretching	[23]
	Gypsum O–H stretching	[19, 20]
	Goethite O–H stretching	[21, 22]