What era is this button/pin/brooch?

[history preserved]

So I found this thing near a second Seminole war fort, but the house I was detecting was built in 1913. It has a roman soldier looking face on it, and has an iron back. Anyone know what this is and how old it is?

 

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[Breezie]

I really can't see the back that well, but it could be a button cover since there are tabs around the edge or it could be a scalloped edge button as shown below. What is the material? Is it light weight? It could be a modern button using an ancient motif.

Welcome to the forum,
Breezie