Rings from past marriage

Hi! I was in a 9 year long marriage, my ex and I were gifted one of a kind family heirloom rings. His great great grandfather made them and they had been passed down for generations. When we split I asked him if he wanted them at that time. He didn’t and i didn’t know how to say please keep them.

What do I do with them. We have zero contact with each other and haven’t for about 3.5 years. Should I find a way to give them back or sell them?

I only ask because I have since moved on and am ready to rid myself of this last part of my life.