Rudrakshas are the seed from the fruits of the trees belonging to Elaecarpus Ganitrus Roxb variety (Rudraksha tree) in Himalayas and in
Rudraksha up to 14 mukhis are mentioned in the Shiva Purana and Padma Purana. Higher mukhis are mentioned in other texts and then there are two or more Rudrakshas naturally joined together like the Gauri Shankar and Trijuti.
Rudrakshas are available in different sizes and the most sought after are those larger in size (15 mm and above). The original ones also have natural hole in it.
Sadly, since there is no authority to check the quality and genuinity of Rudrakshas the market is flooded with artificial and fake beads.
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Benefits attributed to different Rudraksha faces