Antique ruby ring

My grandmother received this as a gift around the beginning of the 1980's. She never specified who it was from, and I along with the rest of the family just assumed it was from my grandfather as they married at 17, and never had any other love interest. When my grandmother passed in 2004, my father was left the ring. He was in possession of it until his passing in 2014, and I am an only child so now it is mine. I'm Just curious to see what if anything it is worth, my grandmother and grandfather were only away from each other for 1 or 1 1/2 years during WWII, and those years are the only blank space in their lives. Upon further discussion with some cousins, the comment was made that the ring was in her jewelry box long before the 1980's.