Madder lake is reported in the literature to have a characteristic pinkish-orange UV fluorescence, both in microscopy cross-sections imaging [1] and UV Fluorescence Photography [4].
Gouache, from the Italian guazzo, is a method of painting with opaque colors ground in water and thickened with gum and honey. The Head of Conservation
I’m sharing in this post the Technical Photography images of my Historical Pigments swatches collection painted with gum arabic. I used a Nikon D800 36