Tiffany semic precious and enamel gold ring - Art Nouveau

SO this Tiffany and co. 18k gold ring was actually dug out of the ground from an old estate. It is clearly marked however the carat stamp is missing - I am thinking this is from resizing (its quite small). At first I thought it was a college insignia ring of sorts. However I have looked through all the insignias I could find and consulted an outside source...
The stones set around the edge are mine cut cornflower blue sapphires. The inside is a combination of royal blue enamel patterning with small stones as well... I'm trying to find out any information about the ring as well as get some ideas as to it's vintage/designer... I was looking through historical timelines for Tiffany and Co. and I could only find one period where semi precious stones and enamel work work were combined. Looking forward to feedback! thanks!