Help Identifying Roman Coin [opgelost]

I bought this old ring at a thrift shop in Rome. It is made of either bronze or copper as it has been turning my finger blue sonce it doesn't have a backing. Any idea what it is or where it's from?

Seems like a copy of a silver coin of Samos. You can find a lot of similar examples in the cataloge: https://en.numista.com/catalogue/index.php?r=&st=1-2-79-80&cat=y&im1=&im2=&ru=&ie=&ca=3&no=&v=&a=&dg=&i=&b=&m=&f=&t=&t2=&w=&mt=&mi=822&u=&g=&se=&c=&wi=&sw=

This looks like the closest match: N#373950