Though she had been made an amaranthine immortal when she was twelve years of age, she'd had to wait for her extraordinary abilities until her body matured to its most perfect state before fully transforming.
-- Kim Lenox, Darker Than Night
It made him jealous to imagine them lost in this amaranthine profundity.
-- Sir Compton Mackenzie, Sinister Street
Amaranthine is a form of the Greek amarantos, "everlasting," ascribed to an imaginary flower that never fades.