Upon being (correcctly) told by Smokeythecat that his maybe-buckle find is actually a shoe heel-plate, Cmthunder replied:
> Farm dates to 1694.
> Pretty small shoe then.
That version of heel-plate, having curved sides, a "cutout" center, and three holes for attaching it to the shoe's heel, is small because this type was made for a Ladies' shoe's small heel. It dates from the 1880s onward (not from the civil war). The one in the photo below has the same shape as yours, except a heart-shaped cutout. A dump-digger found this amazingly well-preserved leather Ladies' fancy High-Top shoe/boot deeply buried in an 1880s town dump in Colorado. You can tell the small size of the heel by comparing it with the rest of the shoe.