Breathing, as well as the rhythm of a heartbeat, is a repeating process, which forms a perception of time as a subjective reflection on the duration of events. Breath is what makes us alive.
The form of the object allows one to take it with both hands as something valuable. On the surface of the mirror, time is indicated by a subtle hour hand, only if the user breathes on it. Breathing of the user not only creates time but also proves that the user is alive and not frozen in stasis.