Fig. 1

Representative FORS spectra in four different binders of a a cochineal pigment extracted from silk shearings (C-Silk), and b a madder pigment extracted from the root in an alum solution (M-Std-Al ex.). For both pigments, despite some change in the shape of the reflectance spectrum with different binding medium, there is no appreciable change in the position of the n → π* absorption features