Posted this story elsewhere a few months ago, but will retell it here.
A couple of years ago I was in about a foot of water at the shore of a large lake near here and used my sand scoop to retrieve a target. I missed the target but found a boar's tusk in my sand scoop. The lake is surrounded by housing, no domestic pigs and no wild pigs ever get near the water, so how did the tusk get into the lake? Not as weird as many things already posted here, but I still wonder how that tusk wound up in the lake. Ah, sweet mysteries of treasure hunting!