Flawless 76-carat diamond fetches $21.5 million at auction

A huge, internally flawless diamond from India's fabled Golconda mines was sold at auction in Geneva on Tuesday night for 20.355 million Swiss francs ($21.48 million), Christie's said.

The rare, colourless stone weighing 76.02 carats once belonged to Archduke Joseph August of Austria (1872-1962), a prince of the Hungarian line of the Habsburgs.

The diamond was the star lot at Christie's semi-annual jewelry sale in Geneva, where more than 300 lots were on the block.

'Pure and clear'The flawless diamond was expected to fetch roughly $15 million when it hit the auction.

“It can be hard to visualize exactly how big a 76.02 carat diamond is,” Christie’s Head of Jewelry Rahul Kadakia told “It's about the size of a quail's egg, and completely pure and clear in color.”

The diamond expert brought the gem to TODAY on Oct. 12 along with other items up for auction, including a watch owned by Eric Clapton and a 100-carat pair of yellow and white diamond earrings.

“This thing is huge,” exclaimed TODAY host Matt Lauer as the diamond was unveiled.

“You told me not to drop it, but I said, ‘aren’t diamonds the hardest substance in the world?’” he asked.

“They are hard but they are also brittle,” Kadakia warned as the more than 400-year-old stone was passed around with care.

Famous mineThe gem comes from India’s now closed Golconda mine, sharing its origins with the most illustrious and famous diamonds in the world, including the Koh-i-noor, in the Royal Collection at the Tower of London; the Regent, which is considered the finest diamond in the French Crown Jewels, at the Musée du Louvre in Paris; and the Hope, at the Smithsonian Institution in Washington D.C.

Known for their special whiteness, Golconda diamonds are universally recognized as the best in the world.

The Archduke Joseph Diamond “is the finest and largest stone from the Golconda mines available for sale today,” said Kadakia.Prices for rare and exquisite diamonds have soared in recent years as increasing numbers of investors buy them as collectibles.

The current leader is The Graff Pink. The exceptionally rare 25-carat pink diamond was sold for more than $46 million in 2010 to London jeweler Laurence Graff who named it after himself.

Graff also bought the world’s second most expensive diamond in 2008 for more than $24 million. The Wittelsbach Diamond is a 17th century sky blue gem that was once given as the wedding dowry of a Spanish princess.

The sale of Elizabeth Taylor’s 33-carat diamond ring last December highlights how quickly records are being eclipsed. Given to her by her husband Richard Burton, the ring fetched $8.8 million, briefly setting a new per carat record for a colorless diamond that has already been beaten.

Noble lineageChristie’s Kadakia told the TODAY hosts that the diamond’s Golconda heritage paired with its noble lineage were “a very big deal.”

Although it is not known exactly when the diamond entered the House of Habsburg, it was officially recorded as the property of the Archduke Joseph August.

It is believed that he passed the diamond on to his son Archduke Joseph Francis in 1933 when records show him depositing it into the vault of a Hungarian bank.

An anonymous buyer purchased the stone three years later and left it in a safe during World War II, where it fortunately escaped the attention of the Nazis.

After disappearing from the world stage for decades, it reappeared at a London auction in 1961.

It was last sold at a Christie’s auction in Geneva to an anonymous buyer in 1993 for $6.5 million.

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