Raw umber
Used throughout history, it has different earth tones depending on the amount of iron and manganese compounds.
Manufacturer / product code: Kremer / 40610
Chemical description: natural mixture of iron and manganese oxides and hydroxides. Brown earth, from Cyprus. Kremer PDF
Color: brown
Color Index: PBr8
More info: Pigments Through The Ages Colourlex
Raman spectroscopy
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”
XRF spectroscopy
XRF Spectroscopy Pigments-Checker Database
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.
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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