In ancient times, most transactions did not involve money at all. That is the big difference to the modern era. Generally, the gold/silver value was really hard

In ancient times, most transactions did not involve money at all. That is the big difference to the modern era. Generally, the gold/silver value was really hard to determine, but minted coins could be more valuable than their believed metallic value: they had exchange value dealing with the regime. I strongly recommend David Graeber's "Debt: The first 5000 years", which is an anthropological account of the changing role of debt and money around the world over history