Stand heavy mirror on its corner
The mirror is too heavy to hang from the wall.


No, its not.  You can hang 300+ lbs on a wall.  Find the center line of a stud and use the proper fastener.

Even without a stud, a couple high quality dry wall anchors would hold up 50 lbs easily.


  It seems a more uncommon setting than I thought. 


Because it's a good way to break the mirror.