In a narrow sense, coinage should mean that there is a gap between precious metal paper money and the issue reserve, that is, it will be distributed randomly. Coin is a market force to maintain parity. The supply of paper money is realized by compulsory means. For example, gold and silver have the same value in any country. Non-world currencies are only valuable at home. The ruling class can issue additional money to manipulate the exchange rate or over-issue money to collect wealth, and then maintain purchasing power by transferring property abroad. Think about how not to easily lead to inflation.