Identifying Your Vintage Silver Ring with a Black Stone

Question
I've had a old silver(?) ring with what looks like a oblong black stone on top.here are numbers on the inside of the ring, 225 ?

Answer
Good morning James, Hmmm...not familiar with 225. Could it possibly be 925 which is the standard purity stamp designation for Sterling Silver being .925 parts pure? Silver is soft and if the ring is old part of the stamp might have worn away. Hope this helps. Good luck.

Steve Kretser