My first find with my Garrett AT Pro...now have no clue as to what it is? It is a couple of inches in length and has writing on it. One word PATD which i think is for Patent of some sort. Anyway it was fun to find.
I think older than the fifties. Just dug the same one from a house in the 20's or so. Dig them from houses in the fifties all the time and they don't look like this one.