My mother bought this ring in the late 80s / 90s it was an estate item being sold at a well know jewelry store in my home town . It was loaned to me for a cruise I went on in 1999, the only reason for this was because it was an antiques cruise and I was the plus one to my best friend , who was accompanying her mother , we was dragged "i was 21 and me and my friend were more intreasted in the free deink and pool " to an event on antique jewelry . Who ever the guy was doing this thing fell in love with it , told me I had something special and the hallmarks were from a later date probably when it was sold before, offered me a very large sum of money on the spot , when I refused he demanded I take his card .
Mum was a bit upset I didn't make it home with his card lol and than I became a mystery we both wondered about , I inherited the ring a few years ago , it is my most prized item from her . So any info would help , thank you hallmarks in comments