CNN  — 

Over the last 300 years, it’s passed through the hands of royals from four European dynasties. But in May, the 6.16-carat Farnese Blue diamond will go on sale for the first time in its history at a Sotheby’s auction.

The pear-shaped fancy dark grey-blue diamond was unearthed from the Golconda mine in India, where the Hope Diamond discovered. It was originally gifted to the Italian-born Elisabeth Farnese, queen of Spain, in 1715, following her marriage to King Philip V of Spain.

It would be passed down through more than seven generations and, as Elisabeth’s descendants married into other European families, journey across the continent, traveling from Spain to France, Italy and Austria.

Courtesy Sotheby's
The Farnese Diamond is being sold with a detachable fitting, a case and a plaque explaining its provenance.

At key points it adorned a tie pin belonging to Charles II, Duke of Lucca, and a tiara dressed with diamonds thought to have belonged to Marie Antoinette. And yet, for much of history, the diamond was known only to family members and the jewelers who tended to it.

‘Fragments of history’

Next month, a family descended from Queen Elisabeth will be selling the stone at Sotheby’s Magnificent Jewels and Noble Jewels auction in Geneva, with the upper estimate set at 5 million Swiss francs ($5.27 million).

However, David Bennett, chairman of Sotheby’s international jewelry division, suggests that the diamond could sell for more: 75% of the jewels sold at 2017’s Magnificent Jewels and Noble Jewels sales exceeded their top estimate.

courtesy christies
The "Aurora Green" is the largest Fancy Vivid green diamond ever sold at auction. The stone went under the hammer on May 31, 2016 at Christie's auction house in Hong Kong, selling for $16,818,983.
Christies Images Ltd 2016
The world's largest blue diamond, an extremely rare gem known as "The Oppenheimer Blue", sold for $57.5 million at Christie's Geneva May 18, 2016, making it the most expensive diamond ever sold at auction.
Christies Images Ltd 2016
The 14.62 carat Fancy Vivid stone is mounted on a platinum ring and flanked on either side by a trapeze-shaped diamond.
courtesy sotheby's
'The Unique Pink' is the largest Fancy Vivid pink pear-shaped diamond to ever be offered at auction.
courtesy sotheby's
The diamond was sold for $31.6 million by Sotheby's, at an auction in Geneva. The price makes it the most expensive Fancy Vivid pink diamond to sell at auction.
Bloomberg/Bloomberg/Bloomberg via Getty Images
Cubic zirconia replicas of the original and a modern cut of the Kohinoor diamond, one of the oldest and most famous diamonds in the world.
CNN
The De Beers Millennium Jewel 4 has broken auction records in Asia.
courtesy sotheby's
The stone sold for $31.8 million, which makes it the most expensive piece of jewelry sold at an auction in Asia.
Sotheby's
Sotheby's auctioned this 9.54 carat ring it says belonged to child star Shirley Temple on April 19, 2016. Though it was expected to fetch between $25 million and $35 million, it failed to sell.
FABRICE COFFRINI/Getty Images
This 12.03-carat blue diamond fetched $48.4 million at auction on November 11, 2015. It was previously the world's most expensive price-per-carat diamond sold.
FABRICE COFFRINI/Getty Images
The fancy, vivid blue diamond was discovered in South Africa in January last year.
EMMANUEL DUNAND/AFP/Getty Images
In recent years, other high-value diamonds have hit the auction block. The 59.60-carat oval cut pink diamond known as "The Pink Star," went for $80 million at a 2013 Sotheby's auction. However, after the buyer defaulted on payment, it was returned to Sotheby's.
Peter Macdiarmid/Getty Images Europe/Getty Images
This 118.28 oval white diamond became the largest sold at auction when it went for $30.6 million at a Sotheby's auction in 2013.
Courtesy Sotheby's
In April 2015, a 100-carat, emerald cut, D color, internally flawless diamond -- the largest of its clarity and cut to ever be shown at auction -- sold for $22 million.
FABRICE COFFRINI/AFP/Getty Images
The 76.02-carat 400-year-old Archduke Joseph diamond set a new record for price per carat for a colorless diamond in 2012, when it sold for $21.5 million at a Christie's auction.
Courtesy Chow Tai Fook
In 2010, Hong Kong's largest jewelry retailer, Chow Tai Fook, bought one of the world's largest rough diamonds for $35.3 million.
Courtesy Chow Tai Fook
Jeweler Wallace Chan and a team of craftsman worked 47,000 hours to transform the stone it into this piece, which Chai Tai Fook estimates could be worth $200 million.

“Royal and noble collectors have traditionally had access to the finest gemstones available, and so the gems which adorn these pieces often display the very highest quality, size and rarity,” Bennett said in an email. “They are fragments of history and there is currently great enthusiasm for jewels of this type.”

The Farnese Blue will go on public display at the Sotheby’s Hong Kong showroom on on March 29, and will be exhibited in London, New York, Singapore, Taipei and Geneva before the auction.