In "Power", Charlotte notices the ring around Nathan's neck and tells him it used to be her husbands. Nathan mentions he doesn't know where it came from, and attempts to give it back, but Charlotte lets him keep it.
In "Just Passing Through", Nathan discovers in 1983 that a woman named Barbara Colton has the ring and it altered her trouble to allow her to create temporary thinnies. The ring had originally belonged to Lucy before Barbara had stolen it. Garland manages to get it back from Barbara and keeps it.