It's a strange site to be detecting. Lots and lots of nails, some really big ones too, almost qualify as spikes. Some areas have some building material remnants, but I'm at a loss as to where it all came from. It's the original church with a newer school building attached at the rear. But the side yard where I am finding the stuff has little or no modern items, little to no trash, and there was never a building of any sort there that I can determine. What I suspect is that the side yard must have been scraped or dug out in the late 40's or early 50's and filled with topsoil from another site. This would explain the lack of items, but what is there is from the 50's and all at about the same 4 inch depth. Only the couple exceptions where I found the few older things are all at the 9 to 12 inch depth.