If a Rudraksha of any mukhi gets a protrusion on its body similar to a trunk of elephant, this Rudraksha is called a Ganesh Rudraksha.
Ganesh Rudraksha bears a Trunk like elevation as is seen on the face of Lord Ganesh, the son of Lord Shiva. Ganesh, the elephant-headed God of success and overcoming obstacles, is also associated with wisdom, learning, prudence, and power. He gives 'Riddhi-Siddhi'. He is the first to be worshipped in the beginning of any auspicious occasion. Ganesh Rudraksha provides the wearer perfection in every sphere in life and the grace of Lord Ganesh is received by him. The Ganesh Rudraksha Bead is really special due to the way it grows the thorny protrusions of the outer surface of the Bead.