Some kind of hair clip?

[Dirtwisher]

It is too stiff for anyone to bend the parts on the back with their bare hands, so that can't be it. The patina looks like copper.

 

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[Ant]

It looks like a lable plate to me.

 

[duggap]

I'm probably wrong but it sure looks like the hooks off the back of a plate.

 

[Honest Samuel]

At my age, I am happy that I still have most of my hair.

 

[Loco-Digger]

I doubt if it's a hair clip. Cool piece though.

 

[pepperj]

Looks more like a mount, used on thick leather.

 

[Dirtwisher]

Looks more like a mount, used on thick leather.

I'm leaning toward this one. Came out of a field so maybe part of a harness setup of some kind