Lejarraga Studio recently designed an un-vanity for a San Francisco penthouse. The owners, who are both mathematicians, opted to gaze into the geologic time of marine organisms etched in stone, rather than a traditional mirror above the sink. A vertical side cove light highlights the elongated geometry of the locally fabricated, Botticino limestone. The floating vanity gives the illusion of levity and makes the space distinctly contemporary. The entire bathroom is an impossible spa whose footprint is completely carved from an old pantry under the stairs. Exceptionally compact, attentive design makes the space feel voluminous and airy.