What is the purple dye obtained from lichens?

The purple dye obtained from lichens is known as "orchil" or "carmine," derived from specific species of lichens such as Roccella tinctoria. This dye has been used historically for textile coloring, particularly in the production of purple fabrics, which were highly valued in ancient times due to their rarity and vibrant hue. The process of extracting the dye involves soaking the lichens in alkaline solutions, which releases the colorants. Orchil played a significant role in the dyeing industry before the advent of synthetic dyes.