Unknown Goblet That Can't Be Reached (Dragon Age: Inquisition)

I ran and ran along the Western Limit and found a hole, and in it this luminous goblet, ran from all sides, (it is possible to stand on a stone as much as possible - it doesn’t let it go further, but on the other hand there is an exit from the location) well, I won’t get to it) MB knows who, what is it and what to do with it? :)