Most world (coin) currencies including those of the ancient world are typically round in shape, or so we thought. A recent discovery has upended that assumption courtesy of ancient Greek coins from the former Greek city-state Olbia from around 500 BC. Olbia used money which was in the shape of a leaping dolphin, like the one shown in the picture alongside! They were the size of 3 cm. Ancient Greek Olbian Dolphin Money The reasons why they issued such unique shaped dolphin money is attributed to the large population of dolphins near the Black Sea and the Olbians saw them daily in the sea and trained them for their amusement. Another reason could be the religious significance, as Greeks considered Dolphins as a sacred fish ‘Delphinus’. It is said that once a dolphin helped Poseidon to locate his mermaid wife Amphitrite and get back to his golden palace. As a reward, Poseidon placed the dolphin in the constellation Delphinus. This series was minted from the fifth to third centuries BC and includes many varieties of some rarer issues with legends. Most of the dolphins are rather crudely cast but the better specimens show dorsal fins and eyes as well as a mid fin that runs along the body.