One of the novel features of Bitcoin and other cryptocurrencies is that coins can be irrefutably "burned" or destroyed, by creating a transaction to send the money to a junk burn address.
Thinking similarly about quantum money - from knots, or hidden subspaces, Wiesner's currency, BBBW, etc. - has an "obvious" way to be destroyed. For example, given a legitimate Wiesner coin, by measuring in the "wrong" basis, the currency would be destroyed.
But it's not clear how to irrefutably prove that the coin was destroyed.
For example, if I have a Wiesner coin, and I tell the world that I've burned it, is there a way that I can do it so that others will believe me? Even if I'm the bank?
I think I first heard of this question in a fascinating and stimulating lecture by Or Sattath - https://www.youtube.com/watch?v=Zd5tDyPXsIM - at around 59:20.
As Meowwzz suggests, clearly measuring a coin in a burn basis will burn it. That burn basis can even be orthogonal to the valid basis, maximally destroying the coin, I think.
Another option that comes to mind is for the bank to publish and broadcast, on a public classical channel, the correct basis for a serial number $s$. Thus, the secret is released, enabling anyone to clone the coin at will, and effectively destroying the unclonability, and hence uniqueness and value, of the coin.
Such an option (on a classical channel) is viable for Wiesner's coin, and the Hidden Subspaces coin, but I don't think for the Quantum Knots coin - there's no secret to be released on the Knots coin.
However, such an option can only be done by the bank or whoever knows the classical secret, whereas I think Meowzz's approach can be done by anyone, including the holder of the coin of interest.