@Spaniard for informing me about it. The inscription is unclear and I'm not even sure whether it's in Greek or Latin. I am sure it's Faustina II. It's 22 mm and weighs 5.83 g. An old collector's tag attributes it to Poroselene, but I'm not so sure that's correct. It features a youth (Taras? Cupid? Melicertes?) riding a dolphin, swimming left, reminiscent of the silver coins of Taras. There is a coin of Poroselene with a youth riding dolphin reverse, RPC IV.2 10103, but the dolphin is swimming right and the style is very different. Moreover, the reverse inscription on that coin reads ΠΟΡΟϹƐΛΗΝƐΙΤΩΝ, and I don't think that's compatible with the few letters on the reverse of my coin. I tried searching for "Poroselene" at RPC to see if the reverse appeared on other coins of this city, but to no avail. I know that Corinth issued a number of coins with dolphins, including a few depicting Melicertes riding a dolphin, but an RPC search for "Corinth Dolphin" yields nothing similar, nor does a search for "Faustina Dolphin." I need help with this one. Thanks in advance!