The roots of MADDER (Rubia tinctorum) give this beautiful blood red thanks to the presence of many coloring molecules, going from orange to purple, passing through red. The most famous of these ones is alizarin, which was also one of the first colors to be sintesized in laboratory. The other coloring principle is purpurin, which has a lower fastness than alizarin. Since it is an alumina lake, its covering power is not high, but it owns a great transparency and brilliance. It is the natural color which was mostly used in the past, beyond indigo, to prepare pigments for artists, due to its fastness too: the obtained pigment owns an extraordinary brilliance and transparency.
Colouring agents: Alizarin and purpurin
C.I.: NR 9