That is mystery metal.
Check it with file to see whatever it is cast - cut a bit and then put white paper to it - if it darkens it then its cast.
It could be a piece of a pad for a fence.
Nice find but did you look around for more! Lol
So how went your bird hunting?
A total bust, didn't fire a single shot between the three of us. The dog brought us a cripple and ran one down way out of range to get a shot off. Lots of people out but no birds.
The day with pals is well worth the outing and you found mystery steel. I would like to bet it's mild steel give it a small drill or file test.