The world's first real gold coin.
The oldest currency in the world dates back to more than 2,574 years ago. It is a coin that was minted from gold and silver together, and after that many coins were minted. The use of coins continues to this day, with the metals used for this purpose differing greatly. As for paper currencies; Its history is later than that of coins.
Having pioneered the refining process to separate electrum into pure silver and gold, the Lydians under King Croesus introduced a revolutionary system of bimetallic coinage around 550 BC.
Croesus' gold stater, worth ten corresponding silver staters, depicts a roaring lion facing a bull - It may represent the royal lion of Lydia leaping to attack its neighboring Greek city-states, symbolized by the bull of Hellenistic Zeus.
Source: websites