The watercolor WELD YELLOW is prepared from Reseda luteola, a weed which is widespread all over the World. It gives a bright yellow color, not very intense, but really transparent. Luteolin is the molecule (a flavone): it is the most lightfast organic natural yellow. This color was often used in the past, both alone, and together with blue obtained from indigo.
Colouring agent: Luteolin
C.I.: NY 2