On each Rudraksha bead vertical lines are seen running down its surface. These lines are called Mukhis or ‘the clefts or furrows on the surface’ and determine the types of Rudraksha mukhis. For instance, Rudraksha beads with one vertical line are one Mukhi Rudraksha, those with two lines are called two Mukhi and so on. Rudraksha beads can have between 1 and 21 faces, but some have been reported to have as many as 26 or 27. The number of faces on a Rudraksha stone determines its significance and the purposes for which it is used