Figure 2From: Winsor & Newton original handbooks: a surface-enhanced Raman scattering (SERS) and Raman spectral database of dyes from modern watercolor pigmentsSERS analysis of cochineal-based pigments. (a) SERS spectrum of reference carminic acid compared to examples of SERS spectra obtained from Winsor & Newton cochineal-based pigments (λexc = 488 nm): (b) crimson lake 20th century edition, (c) crimson lake 19th century edition, (d) scarlet lake 19th century edition, and (e) dragons’ blood 20th century edition.Back to article page