Similar to Isaac's unlisted question, but with slightly different criteria.

Such a cryptocurrency would need to include the following features:

• The ability to spend a coin depends only on possession of some quantum "token".

• Tokens must be publically verifiable

• Anyone with a fault-tolerant quantum computer and a token can transfer the token to anyone with another quantum computer, as long as they can transfer quantum data

• Starting with a certain amount of money, it is infeasible to double-spend or create more money.

• Finalization of transactions in any location takes less than 10 minutes.

• Based only on well-accepted post-quantum cryptographic assumptions at the time the design is released (recursive SNARKs and lattice-crypto are examples of things currently ok as long as they don't get broken, money-from-knots is not currently ok, but could become ok with stronger justification)