Eyup Mr Wulluff, I've not been, much to my chagrin. I spent quite a few yomps around Hexhamshire Common, as I have gut feeling there should be RA up there somewhere, but missed that one.
The three marks look a bit iffy, more like those quarry marks you often see on outcrop panels, but why would anyone put them on a relatively small stone like that? Mr Rockrch may be the man to ask, it looks like he's been up there.
Nice Buttony pics btw.