Antique Sterling and Gold Victorian Snake Ring

I found this little beauty today. At first I didn't want to buy it because it is so delicate. I only wear big jewellery because I always break things. Then I thought, maybe one of my daughters will like it - if I don't tell her it is a snake. But then I had a second look at it when I came home.

The ring is small. There are two marks on the outside of the band but they are too small for me to read. The ring was sold as an amethyst but I believe it might be a light-coloured ruby. The stone looks like it is supposed to be the open mouth of the snake, and it is surrounded by gold.

I believe that the snake is a symbol of eternity or eternal love, popular during Victorian times.

Thanks for looking:)