Please help with Civil War US belt buckle, real or fake repro?

Hi. Any opinions on this being a fake Civil War era buckle? I am unsure about the ridge along the edge of the back. Someone went to a lot of work to fake it if it not authentic. Thank you for any help and opinions.

 

I don’t know.Certainly looks old and as if it was dug out somewhere (or left outside,big condition difference between the back and front) Overall the back makes one automatically think it must be authentic. Looks like there were a few versions in terms of how the buckle was attached to the belts (this looks like 1839 era model?) However what is your buckle made off? (the corrosion on the back makes me think of iron) From what I read the originals were made of brass and lead (lead-filled brass) I really don’t know but Im a little suspicious.

But also why would someone go to all this trouble to fake something that’s not that valuable in the first place!?

Looking forward to hearing what the knowledgeable members say..

 

It does look like a thin layer of metal that has been filled with another metal, and the white oxidization may indicate a lead component, but just spouting an opinion based on your photos and what @Boland wrote.

 

Check the hook and studs on the back with a magnet. If non-magnetic, it could be that it was resting on something iron that leached the rust onto the stud and backing lead.

 

I believe lead filled with corrosion..and a great original buckle