as a token

as a token (of something)

symbolic of something, especially of gratitude; as a memento of something. He gave me a rose as a token of his esteem. Here, take this gift as a token of my appreciation.
See also: token
References in classic literature ?
Leave no black plume as a token of that lie thy soul hath spoken
However, on the third night the soldier carried away one of the golden cups as a token of where he had been.