Orcein

Nome científico: Roccella tinctoria
Família: Roccellaceae
Género: Roccella
Espécie: R. tinctoria

Is a lichen that grows on the rocks of the islands of Macaronesia, which was exported from Cape Verde until the mid 19th Century, as a dye was extracted from it (litmus blue), which was used to dye cloth until the appearance of industrial chemical products.