Sepia
The ink sac of cuttlefish supplies a brown dye called sepia.
Manufacturer / product code: Kremer 12401
Chemical description: 78% melanin, 10% calcium carbonate, 7% magnesium carbonate, 2% alkaline sulfates and chlorides and 0.8% miscellaneous compounds.
Color: brown
Color Index: NBr 9
More info: Kremer PDF
It was used in the 18th century as a brown pigment in ink painting, illustration and calligraphy.
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
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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