Can't make out the insignia but it looks like a cap badge.
Agree. It looks like a cap badge. We need betters pictures of the symbol.
Is it this?
View attachment 1307409
I don't think its a capbadge. It has some age to it, at least 200+ years & was meant to go on leather. So its most likely is a horse harness mount.
Is it solid metal and heavy, or stamped from thin metal ? A stamping wouldn't be 200 yrs old.
Was there any WW1 action there?