Even engagement rings I think can be kept by the woman, can't they? At least that was the thinking, I have always believed, though who would really want to keep a reminder of a failed engagement?
And this was a woman, Laci, who was married for 5 years--not to mention of course some of the stones came from her own grandmother, apparently. The Ps have a lot of gall. Those rings/diamonds belonged to Laci, no matter what.
Not unless you marry and then they become part of the wedding set.
If the engagement is broken, regardless who breaks it the ring goes back to the person who bought it.
I know this because I watched a court case in regards to an engagement ring.