What is the history of 'Sengol', that'll be placed in new Parliament?

PM Narendra Modi will install the golden sceptre, Sengol, in the new Parliament building on May 28. It was used on August 14, 1947, to mark transfer of power from British to Jawaharlal Nehru. The high priests of a leading Saivite Mutt in Tamil Nadu have blessed it. Notably, the Sengol signified the transfer of power in the Chola dynasty.