Rings true

My mom and aunts have slowly been going through my grandparents' things since they passed away this past year. It's definitely an opportunity to reminisce and guess at the stories behind some of the items. While I was home, my mom showed me some of the jewelry that had belonged to my grandparents and my great-great aunts before them in some cases. She gifted me with a few pieces, including the typing award I showed earlier. One of the more peculiar items was this (men's size) ring. I really want to know the story behind it!

Unfortunately it is not real gold so it turns my fingers black when I wear it!