Indigo
It was used in European easel painting since the Middle Ages. Marco Polo (13th century) was the first to report on the preparation of indigo in India.
Manufacturer / product code: Kremer / 36005 (V.1); Kremer / 36000 (V.2)
Chemical description: fermented extract from the leaves of indigofera tinctoria, precipitated with aluminium hydroxide. Kremer PDF
Color: blue
Color Index: NB1
More info: Pigments Through The Ages Colourlex
Raman Spectroscopy 532 nm – ElviRa Spectrometer for Art
Raman Spectroscopy 532 nm (ElviRa spectrometer) Pigments-Checker Database
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Raman spectroscopy 785 nm
Pigments (powder, no binder)
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Raman Spectroscopy 785 nm Pigments (pure, no binder)
Pigments with acrylic binder (Pigments Checker)
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Raman Spectroscopy 785 nm Pigments-Checker Database
Pure pigments (no binder, just powder)
DOWNLOAD paper: “Pigments Checker version 3.0, a handy set for conservation scientists: A free online Raman spectra database”
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Raman spectroscopy 830 nm
Pigments (powder, no binder)
Raman Spectroscopy 830 nm Pigments-Checker Database
Raman spectroscopy 1064 nm
Pigments (powder, no binder)
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Raman Spectroscopy 1064 nm Pigments-Checker Database
XRF spectroscopy
XRF Spectroscopy Pigments-Checker Database
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DOWNLOAD previous database from Pigments Checker V.3 DOWNLOAD paper: R. Larsen, N. Coluzzi, A. Cosentino “Free XRF Spectroscopy database of Pigments Checker” Intl Journal of Conservation Science.
Reflectance Spectroscopy (200-1000 nm) – GorgiasUV Spectrometer
Reflectance Spectroscopy (200-1000 nm) (GorgiasUV) Pigments-Checker Database
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Reflectance spectroscopy – Gorgias Spectrometer for Art
Reflectance Spectroscopy (350-950 nm) (Gorgias) Pigments-Checker Database
NIR Reflectance spectroscopy
NIR-Reflectance Spectroscopy (930-1690 nm) Pigments-Checker Database
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FT-IR Spectroscopy (Non-invasive Diffuse Reflectance Probe)
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FTIR Diffuse Reflectance Spectroscopy Pigments-Checker Database
FTIR non-invasive Spectroscopy Pigments (pure, no binder) Database