hello
I see you've put up a photo of the stone.

I'll admit I don't know anything about quarrying / geology. It was just that I noticed the very parallel lines on the side of it. I know some rocks would do this anyway, but isn't this made out of some hard granitely cornish thing? and if so, they won't be weathering? so could they be traces of how it was cut out the ground?
Just asking, I don't know if there's enough on the photo for people to say.?