Round shape one mukhi rudraksha, you will get 100% chance to purchase fake one. I have been searching from last 6 years and studies lot things about rudraksha specially round shape one mukhi. I have purchase 8 to 9 round shape one mukhi rudraksha after testing all become fake one. if you want to see original round shape rudraksha go to Pashupatti temple at nepal and Jaganath at orissa, both rudraksha under security of Police.
I had been visit and see then I feel , It look like hart of earth ...really amazing
It is my experience