Those look like gold coins. If that's the case then those coins can't be regarded as fiat currency because the gold itself has value.

This is the definition for fiat currency: A fiat currency is a national currency that is not pegged to the price of a commodity such as gold or silver. The value of fiat money is largely based on the public's faith in the currency's issuer, which is normally that country's government or central bank.

Lol, this is so funny