The snake or serpent is a symbol of eternity and is also associated with several healing deities, including Asclepios, the Greek god of medicine. The rings were popular throughout the 19th century. A snake ring with emerald eyes was given to Queen Victoria as an engagement ring by Prince Albert. 
A fantastic 14k gold antique snake ring. Featuring a ruby for an eye, this ring has great details all around. Priced $860 and is currently a size 5.75.