The map ref. is only approximate because for the life of me I cannot remember exactly where I saw this. I was reading a post from FourWinds about disappearing Bullaun stones and remembered seeing this some years ago. I took the picture and forgot about it until I read the post and there it was in my archive. FourWinds thinks it may be a Bullaun stone, the hole is about 8ins across and about 4ins deep and I think is close to the Auchengaich burn. I don't know anything about the folklore around here but I shall take another look next year when I drag myself home again.