OK, so we have 2 threads with this ring now, but I'm going to reply on this one cuz it's newer. Can you tell us the size? Is it adjustable? What 3xflyfisher said: what's it made of? If it's a man's ring, made of good metal, then we should go off into fraternal orders, college rings. If it's cheap metal, maybe a premium from an old radio show? Philo Vance was a popular detective back in the day, but as he was suave & upper class, the whole pirate thing may not fit him, but I don't have a site for old radio show premiums.
The chase is on!