|Semi-autonomous AE20 of Kyzikos in Mysia.|
It's a coin from Kyzikos (or Cyzicus in a more Latinised spelling), a long-gone town whose ruins are visible at Bal-kiz in Turkey. The obverse side shows the town's patron deity, KOPH CΩTHIPA, Kore the Saviour, who had a part in the mythical origins of the cycle of the seasons. She was a goddess of agricultural fertility, and wears a wreath of grain.
On the reverse is a panther with one paw over the mouth of a large vessel. Many descriptions call this a vase, and that makes me wonder how anyone can look at an image like this and not try to decipher what was supposed to be happening. Why would a panther paw at a vase? And there is a very good answer to this question.
It's not a vase. It's a krater, a large vessel used to mix water with wine for evening drinking parties, symposia. These were held to mark all sorts of occasions, or just for an evening of fun. The panther belongs to Dionysos, god of divine intoxication, and it places a paw over the mouth of the vessel to show that the contents belong to the god.
In a symposium, one man would be in charge of the krater from which everyone would dip their drinks. He would manage the strength of the mixture so that brilliant conversation flowed, and no-one would get too drunk too quickly. (That's the theory, anyway!) If you look at the panther's neck, you will see a collar. The panther was under control, and perhaps this means that the symposia were also under control.
The text around this image, KYZIKHNΩN, names the coin as coming from Kyzikos. So this side of the coin seems to be saying that here in Kyzikos, we have plenty to celebrate, and we do it in the proper form. It might even have been intended to refer to one particular celebrated event.
Quite a few ancient coins show kraters, and some of those have a symbol of Dionysos over the mouth. But this is the only coin type I have found which shows a calyx krater, so called because its form resembles the calyx of a flower. Most have the more showy volute kraters, with fancy curling handles rising above the rim.