These underwear are dyed from plants. There are two plants that went into the natural dyes:
Rubia tinctorum: the rose madder or common madder or dyer's madder, is a herbaceous perennial plant species belonging to the bedstraw and coffee family Rubiaceae.
Rubia Cardifolia: known as Indian madder,is a species of flowering plant in the coffee family, Rubiaceae.
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