if we're talking engagement rings,
an engagement ring was the symbol of wanting to commit to marriage, when you no longer want to be married and want to free yourself of that original commitment , why would you hold on to the ring that paved the way to the original marriage? Makes no sense to me, all of a sudden it's just a piece of jewellery but originally it's significance was of the utmost importance - which solidifies my idea that you still don't know what you want.

As for wedding bands, you each got one, returning the rings to each other almost seems like trading the same for the same. Most men don't receive engagement rings and most men ask women to marry them so that's my opinion (read that as opinion) on the engagement ring.

Why would you hold on to something so symbolic?

The right thing to do would be to return it if you're a WAW, if you really want to leave the marriage, leave it, and leave behind those things that were associated with it.

When people are leaving a marriage, they should be respectful if even for that one last time and return items that their STBX spouse wants back, it isn't worth the fight or arguing "I should get to keep it because it was a gift" nonsense, why would a WAS want to keep a "gift" from the spouse they're leaving?

"It meant so much to me at the time..."
and now...
"I'm having it melted and turned into a necklace"

Nonsense.

Return it, start fresh, no attachments to the past.
Use the band-aid analogy, rip it off quickly in one pull, it'll hurt like a bugger but the pain will subside and you'll recover quicker than removing it slowly which will cause even more pain & suffering.

Knittedscarf you're still an enigma to me,
you would be sad to return the ring to your spouse although you seem hell bent on leaving him & divorcing him - methinks your energy is misplaced. You shouldn't be sad for inanimate objects, you should be sad about the things that live & breath - I don't expect a logical explanation, I'm just making a statement. I know you're hurt and in pain in your own way and dealing with this as best as you possibly can for the time being, I wish you the best of luck with that.