What is this?

WWII era?

A fellow veteran's grandfather recently passed. This was found in his security deposit box. Original poster:

Any old Navy vets on my page or anyone who knows one? His Grandfather was a survivor of Pearl Harbor and was a door gunner on a bomber at Midway. This was something left to the family after he passed and they want to find out what it is. Any help would be appreciated.

Bueller?

Update: No update. The vet, or his family, are going to get it from their safety deposit box on Monday and give him some more info. As of right now, from all the people trying to find out, this is either a plumb bob or an elaborate victorian era brooch. Updates soon, I hope.