Archivum:
I don't think this is an Alexandrian issue even though Pius did issue a
tetradrachm with a similar
reverse in year 5. The
style of your Poseidon does not match the Alexandrian one. I would be looking at the "O" to see if it was a theta date, and it does not look that way to me. The backward "S" might simply be a
dolphin, but if that is the case, what is Poseidon holding in
his right hand ?
The only
inscription, other than a date, that would make sense is "POSEIDWN", but even that would be a long shot as the backward "S" on the coin would not resemble the actual Greek letter.
Iwaniw