One Australian woman has answered that question for herself, recently listing her $23,000 Tiffany engagement ring on the private buy-sell Facebook group 'High End'.
"Selling this for obvious reasons. I do now I don't," the seller wrote on the listing.
"Compared to current Tiffany pricing of a 1.0 Carat ring at $23,600, I am letting go of this beauty at $18,500. Condition is close to brand new - never worn much."
The seller explained that the ring would be able to be resized at any time for no cost due to Tiffany's lifetime guarantee on their jewellery, despite not being the original buyer.
"Sorry, no receipt as I didn't buy it, obviously. Bank transfers only," she said.
Daily Mail Australia reported that many in the comments of the listing became argumentative over the legality of the woman who had to sell the ring.
"Legally you can't sell this and have to give it back if you didn't proceed with the marriage," one woman commented.
"If he paid for it, it's his, and he should get all the $$$," another user agreed.
But others came to the defence of the woman, calling out users for assuming the sellers' circumstances.
"OMG, why do [people] feel the need to comment on this? You don't know the circumstances. If you don't want to buy it, why bother adding your two cents?" one person wrote.
It's unknown whether the woman was engaged or married, but what is clear, no one really knows who keeps the engagement ring.
