The mirror is beautiful but was an incredible challenge to hang, as I hung horizontally and the pre-fabricated / mounted hardware was not identical on each side of the mirror.  This is a heavy piece and it's imperative to get it right the first time as the holes it creates in the wall are large and if your measurement is off by 16th of an inch the mount area must be moved and moved far enough away from the original mount that it doesn't cause further damage.  I would highly recommend making the hardware mount on the mirror exact and incorporate a simple cardboard mount template.