To unify the variety of massing, a homogeneous stone covering is used for both floors and walls (and these diagonal planes, which seem to be on the brink of an in-between wall and ceiling).  Photo 10 of 13 in Inside the Musee d'Orsay by Tiffany Chu

Inside the Musee d'Orsay

10 of 13

To unify the variety of massing, a homogeneous stone covering is used for both floors and walls (and these diagonal planes, which seem to be on the brink of an in-between wall and ceiling).