hair swapping?

Hair-swapping may seem a bit strange now, in an age where we can carry basically all of the non-forensic evidence of a relationship—from photos to correspondence to shared transactions—around in our phones. But in the past, and particularly in the Victorian era, swapping hair served as a common sign of affection, a way to literally give a friend, relative, or lover a piece of yourself, and keep a piece of them in turn.

John Keats’s hair, with a note from Leigh Hunt attesting to its provenance. The empty frame probably originally contained a portrait of the poet. Atlas Obscura

VIA