Unique ring unsure of maker

I know this ring is from before 1970. I've been searching and searching for years now to find the person who made it. There is a mark on the outside of the shank there are no marks on the inside of the shank and no metal purity marks with numbers. I tried looking up this Mark and I can't find it anywhere. The ring never tarnishes. It's an interesting ring and belonged to my mother as far as I know. I would love to know more about it.