#TodayILearned that Rose Madder isn’t just the name of a Stephen King book

Wikipedia says that

Rose madder (also known as madder) is a red paint made from the pigment madder lake, a traditional lake pigment extracted from the common madder plant Rubia tinctorum

Picture from Wikipedia - A botanical illustration of a plant with green leaves, yellow flowers, and a red root system, accompanied by detailed sections and diagrams.