Technically, it's Gaz, one of a group of islands making up the Brijuni Islands National Park in Croatia.
But to me, it's a really cool fish-shaped island postcard that looked great sitting in O'Neal's mailbox and even better when it joined O'Neal's fabulous postcard collection!
And, umm, Nives, here is the pretty black stamp again ; )
I really like when the cancellation is clear and legible.
Thanks very much for the nice surprise!