James,
I believe that this might be a 1925 Hindenburg election pin/medal. Hundreds, if not thousands, of these were made and distributed, kind of like a campaign pin. There are many different examples. Can you identify what type of metal this is made of? Some of these pins/medals were made of aluminum, like the common Nazi "tinnies". These would oxidize white and eventually just turn to dust. The detail on this one is very, very rough while most of these had a rather sharp detail. This makes me think that it is badly oxidized aluminum or maybe a copy made from a wax mold.
Just a thought.
John :?