This, believe it or not, is a coin. It’s a coin of the polis of Olbia on the black sea coast, and it is a cast in the shape of a dolphin. In one of the most remarkable currencies of the ancient world, Olbia, literally the wealthy city, according to its name, chose to mint coins in a non-circular form for the first time since the invention of coins. The distinct form is generally attributed to the fact that the city of Olbia, located on the Black Sea, was at the fringes of the Greek world, therefore adapted Greek forms to fit their own needs. The large quantities of finds and the later appearance of dolphins on circular coins have convinced scholars that these were used in exchange.
The symbolism of the dolphin is believed to be religious, since the city held a large temple to Apollo Delphinios, Apollo of the Dolphins, which is also connected to the Apollo at Delphi. The image shown here, taken from a Greek vase, shows Apollo atop a tripod with his lyre, accompanied by dolphins.
The coins are undated through any kind of marking but are generally thought to be the product of the 5th or 4th centuries BCE. They are bronze and are generally a little more than an inch long.