Presently on display in a royal crown in the Tower of London, the famed 106-carat Kohinoor was not gifted to the British but they took it away by force from India, claims historian and author William Dalrymple.
Dalrymple has written a new book with journalist Anita Anand on the "rock star gem" that has a complex history and has been the subject of intrigue and enigma for centuries.
Dalrymple told IANS in an interview that the most famous diamond, now in the Tower of London, "is a symbol of looting of colonial times".
The Scottish historian, who has lived in India on and off since 1989, says they "have successfully cleared facts from the fiction" that fogged the history of the "celebrated imperial trophy".
"There is absolutely no doubt about (how the gem was taken away). It is complete nonsense to say it was gifted by Maharaja Ranjit Singh."
Agrees Anand, a British radio and television journalist and the co-author of the book "Kohinoor: The Story of the World's Most Infamous Diamond", published by Juggernaut.
"What we objected to is this nonsense that people think it was a gift from Ranjit Singh. It was not a gift. When the diamond was taken away, the Maharaja was already dead."
Anand said, in fact, it was Ranjeet Singh's 10-year-old son Maharaja Duleep Singh from whose possession the gem was taken away on March 29, 1849.
"He was a frightened kid. He yielded to the British pressure."
The remarks, which they have established in the book with newly-discovered historical evidence, are significant because the fabled Kohinoor returned to media spotlight earlier this year when India reclaimed it.
However, the government on April 16 told the Supreme Court that the diamond was given freely to the British by Maharaja Ranjit Singh, and had been "neither stolen nor forcibly taken by British rulers".
"This is an unhistorical statement, strikingly unhistoric," Dalrymple told IANS at a farmhouse in Mehrauli on the outskirts of Delhi.
The book is likely to re-catalyse a heated debate whether the rock should finally be brought back to India even as Pakistan, Iran, Afghanistan and even the Taliban have all claimed ownership of the gemstone.
The stone has passed through the hands of Mughals, Iranians, Afghans and Sikhs, and the origin of the diamond surrounded by airily insubstantial fog of mythology is still mysterious.
Anand recalls that the seeds of their work were planted at an event in London's South Bank where Dalrymple invited her and senior Indian diplomat and author Navtej Sarna to speak about the diamond.
"That is when we realised the life story of the diamond and its missing chapters. That is how the journey started. As a journalist and a historian, both of us believe in tracking sources, going back to the scene of crime. We have tried to make it factual rather than fanciful. Our book will be flesh on the bones of the facts."
She says even the British were "uneasy about the way the diamond was taken away from India".
"There was some feeling that it was immoral. They felt guilty. The Queen felt so guilty that she didn't wear it."
And where should the diamond go now as India maintains it will try to get the diamond back despite the British government's adamancy that the stone will stay in London?
"We have not taken a stand and we are not taking a stand. What we are trying is to tell a story -- a multifaceted story like the diamond itself," Dalrymple says.
"You know the Indians want it back, you know the Britons don't want to return it, the Iranians want it back, the Afghans want it back, the Taliban, in fact, want it back, the Sikhs want it back and want it to go to the Golden Temple." And he has a suggestion.
"Maybe we can bring India and Pakistan together if we create a museum on the Wagah Border (where the diamond can be placed) and finally bring peace between them."
He said there is a suggestion that it should be cut up once again and a piece each should be given to all those countries that make a credible argument for its return.
"But let's also understand that this Solomonic wisdom would never be entertained by the British. And, yes, it won't satisfy any of the parties."
(With inputs from IANS)