New finds at Edfu in Egypt show how ancient Egyptian society used grain as a currency. They discovered a huge silo where grain was stored – in effect the bank for the city!
I think this is a useful insight into how ancient civilisation works and a reminder for fantasy world builders that currency doesn’t have to be traditional coinage, but a note of both realism and difference can be brought to world creation by thinking laterally – what would the society actually value and be able to use as a form of exchange.