It's happened before!

"A total of 1000 coins strung together were referred to as a chuàn (串) or diào (吊) and were accepted by traders and merchants per string because counting the individual coins would cost too much time. Because the strings were often accepted without being checked for damaged coins and coins of inferior quality and copper alloys, these strings would eventually be accepted based on their nominal value rather than their weight; this system is comparable to that of a fiat currency."

https://en.wikipedia.org/wiki/String_of_cash_coins_(currency...