cast iron 'edge plate' from a loading dock?

At least I think that's what this old chunk of cast iron was probably intended to be -- some sort of "step" anyway. It is a little short of 11" wide and 7' long with a 4" lip under its front edge, the whole thing cast approx 3/4" thick. Its gotta weigh in the neighborhood of 200lbs (more?) as I can lift either end of it by myself but to move the whole thing requires wheels and/or a helper.

No matter what it is/was, with the addition of a couple carefully placed concrete blocks it now serves handily as a nice sturdy step from my patio to the yard below. Termite proof, even! <lol>