I think it may be from a necklace due to the orientation of the characters on it. But, thinking gets me in trouble most of the time! Maybe similar to this one. I know this one is upside down compared to yours but you get the idea.
Sounds like Mud Hut has already nailed the I.D. Ed, but what intrigues me is the type of metal used.
It looks like cast brass in high-relief... date wise I'm thinking 1910 - 25.
I'm not sure it's a key chain though, I think its from something else due to the square holes at the bottom.