Copper(?) Police button dug at old farmhouse

[Minrelica]

I dug this POLICE button near a tree line between an old farm house and RR tracks. It's nearly the exact size of a quarter and appears to be copper. The back is intact but rough condition and needs some cleaning overall.. Are there any button experts that know the approximate year such buttons may have been used in the Midwest? Minnesota to be exact. Thanks for looking!

 

[vpnavy]

Nice find. Let us know what you find on the back of the button. I searched and found a lot of old buttons but really need to know the manufacture (back of button) to help ID.

 

[Minrelica]

Nice find. Let us know what you find on the back of the button. I searched and found a lot of old buttons but really need to know the manufacture (back of button) to help ID.

Unfortunately, the back currently looks like this. Perhaps I should perform a little (well attended) electrolysis on it tonight, I'm sure that much of the corrosion will drop off pretty quick. I haven't cleaned a button yet and I don't want to mess it up.

 

[Calabash Digger]

cool button.

 

[trapperart]

Congrats on the cool button

 

[dirtlooter]

pretty cool and good luck on the cleaning