Lost Treasure: The Florentine Diamond of the Medici

One of the Most Magnificent Jewels in History, This $20 Million Diamond Remains Lost

Michael East
Sep 24, 2020 · 11 min read

Formerly one of the Crown Jewels of Austria and the prize of the Medici Family, the Florentine Diamond is a nine-sided 126-facet double rose cut diamond, a diamond that has been at the centre of death and mayhem for many of the (un)fortunate few who have owned it. Also known as the Tuscany Diamond, the Grand Duke of Tuscany and the Austrian Yellow Diamond, the stone has been lost to history since 1919, and despite once being sold for around two francs, it would be worth more than twenty million dollars if it appeared at auction today.

Florentine Diamond modelled after the hatpin photo and described by Tillander (left). Second diamond based on a line drawing by Tavernier (right). Photo by Fred Ward

Originating in India, the stone is particularly notable for its pale yellow colour, with a very slight overtone of green. Yellow diamonds are exceedingly rare in the country, with only the Shah Diamond coming close to matching its brilliance at a comparatively meagre 88.70 carats compared to the Florentine’s 137.27.

With its origins often shrouded in mystery and myth, the diamond is said to have been initially cut by the noted Flemish jeweller Lodewyk van Bercken, inventor of the scaif. This polishing wheel is infused with a mixture of olive oil and diamond dust that makes it possible to polish the facets of a diamond symmetrically at angles best reflecting the light. The invention revolutionised the diamond industry, making cuts never before seen possible and producing, amongst others, the Florentine Diamond. If the stone’s 15th-century origins are indeed correct, the diamond is likely to have originated in the river basins on the eastern side of the Deccan Plateau, possibly the Sambalpur mines.

Charles The Bold, Duke of Burgundy between 1467 and 1477, became a patron of van Bercken and, noting his skill, asked the jeweller to cut the 137 carat stone. Charles is said to have been wearing the same stone when he fell at the battle Battle of Nancy in 1477, having been in the habit of wearing it around his neck as a good luck amulet. It didn’t bring him any luck this day however as the Burgundians were handed a crushing defeat by the Swiss Confederate army, ending in the death and mutilation of Charles. According to inventories of Charles’ possessions, the Duke owned three large diamonds, of which one was “as big as a walnut and yellow in colour.”

Tombs of Charles the Bold and his daughter Mary of Burgundy in Onze-Lieve-Vrouwe Kerk in Bruges, Belgium

Found by a common soldier, the diamond was allegedly sold as glass to the city of Bern for Three Guilders, the city selling it on to one Bartholomew May for Five Thousand Guilders once they had realised it was a diamond. The stone was sold on to the City of Genoa for Seven Thousand Guilders and from the Genoese to Ludovico Sforza, the Duke of Milan and patron of Leonardo Di Vinci. The providence of the diamond only continues to grow as it’s legend and value starts to become apparent, becoming one of the prize jewels of the super-rich of the age. The diamond passed on from Sforza to Jacob Fugger of the Fugger banking family, to Pope Julius II and then either to the noble Portuguese Castro-Noronha family and then into the hands of Ferdinando I de’ Medici, Grand Duke of Tuscany, de Medici, or directly to the Duke.

However, another theory states that all of that is absolute nonsense, mere myth and legend and that the actual truth is that the diamond has its real origins in the Portuguese conquest of Goa by Afonso de Albuquerque in 1510 and with the ruling royal dynasty. If correct, the diamond may have originated in the Kollur mines of Golconda rather than the Deccan Plateau, these mines only being worked from the 16th century onward.

Through the compelling research of art historian Nello Tarchiani in the 1920s and through the work of Speranza Cavenago Bignami, Guido Gregorietti, Herbert Tillander and P. Aloisi, it was discovered that the uncut gem had been seized from the King in late in the 1500s. It was taken by Ludwig Castro, Governor of Goa and Count of Montesano, gifting the jewel to his wife, Mexia de Noronha. The diamond was entrusted to the Jesuits with instruction to sell it, and in 1601 it was indeed purchased by Ferdinando I de’ Medici. Cosimo II de’ Medici, son of the Grand Duke, employed a Venetian diamond cutter working in Florence by the name of Pompeo Studentoli to cut the diamond in 1615, not Lodewyk van Bercken as the legends claim. The Florentine Diamond was delivered to de Medici on October 10, 1615, and an inventory drawn-up on Cosimo’s death confirms the acquisition and describes the stone as “faceted on both sides and encircled by a diamond-encrusted band.”

Yet a third tradition states that upon the death of Charles The Bold, the diamond was part of the war booty seized from the city of Basel, being acquired by Henry VIII of England in 1574. Remaining in England until 1558 and the death of Mary, the jewel ending up in the collection of Philip II of Spain. This telling of the legend, however, doesn’t tell of how the gem ended up in Austria. It is most likely a fabrication.

Confirmed history for the stone begins in 1657 when the noted French traveller and jeweller Jean Baptiste Tavernier observes the diamond amongst the possessions of Ferdinando II Medici, the 5th Grand Duke of Tuscany and son of Cosimo II. Tavernier makes several drawings of the impressive stone and subsequently in 1676 publishes them in his book, The Six Voyages of Jean Baptiste Tavernier. Tavernier stated that the diamond was the largest in Europe at the time of the book’s publication, he gave the then nameless stone the name “Florentiner.”

Passing from son to son, the diamond passes through the hands of Cosimo III de Medici and finally Gian Gastone, the last of the Medicis. Dying without an heir, the Grand Duchy of Tuscany passed into the hands of Vienna with the Dukes of Lorraine and Francis I Stephen of Lorraine who became Grand Duke in 1737 and Holy Roman Emperor in 1745. The Florentine Diamond thus became part of the Hapsburg Crown Jewels in the Hofburg, Vienna, its valuation was $750,000. It is also here that the diamond gets regains its name, once again named “Florentine” by Francis’ wife Maria Theresa, named so in honour of it’s Medici past.

In 1770, Francis gifted the jewel to his daughter Marie Antoinette as a wedding present, the bride wearing the gemstone when she married the then Dauphin of France, the future Louis XVI. Following the French Revolution and the execution of the royal couple in 1793, the diamond vanishes from view before eventually again ending up in Austria.

The Wedding of Marie Antoinette and Louis XVI

Upon the marriage between Napoleon Bonaparte of France and Marie Louise, Duchess of Parma, Napoleon made a wedding present of the Florentine diamond. Following Napoleon’s abdication and exile to Elba in 1814, Marie Louise was dissuaded from joining the former emperor by her advisors and under the advice of her father, Emperor Francis I of Austria, the Duchess returned to Vienna in April, taking the Florentine with her. Francis had the famous stone set into the crown of Habsburg, remaining there until 1888 when Franz Josef, Emperor of the Austro-Hungarian Empire had it incorporated into a necklace for his wife Empress Elisabeth, commonly known as Sisi. The trail of death in the diamonds wake, from Charles The Bold (allegedly) to Marie Antoinette, would seemingly continue as Sisi was assassinated by Italian anarchist Luigi Lucheni in 1898. After this, no Habsburg wanted anything to do with the diamond, and it went on public display in Vienna as part of the Austrian Crown Jewels. Set into a hat decoration, the diamond was exhibited in case XIII and noted as remaining the property of the Habsburgs.

In 1916, with Austria-Hungary embroiled in the First World War, Charles I of Austria and the IV of Hungary ascended to the throne, seeking to remove the empire from the war. He lost immense support following his support for French claims on the region of Alsace-Lorraine, renouncing power in the November of 1918.

On the evening of October 31, 1918, and into the morning of November 1, before Charles renouncing power, Lieutenant-Governor Leopold Count Bechthold completely emptied display case XIII of the treasury, thirty items in all. The upper chamberlain also removing eleven diamonds and gemstones from case XII, transferring the valuables to the Schönbrunn Palace. In all, eight or nine Orders of the Golden Fleece inset with diamonds, emeralds and rubies, four decorated stars of the Austrian Order, a star of the Leopold Order decorated with white and yellow diamonds, Queen Elizabeth’s diamond crown, watches, rings, bracelets and necklaces were all taken alongside the Florentine diamond.

Grand Duke Charles of Austria, the later Emperor Charles I of Austria (R 1916–1918) | Bain News Service, publisher

The jewels were brought to Switzerland on November 4 by Count Bechtold, the count being arrested at the Vienna Westbahnhof by communist rail workers invoking an imperial law prohibiting the export of valuables in time of war. After a police consultation, the count was released and allowed to travel on to Zürich. He deposited the jewels in the safe of the Schweizerische Nationalbank. It is here that Bruno Steiner, lawyer and former financial advisor to Franz Ferdinand, enters the frame, being entrusted with the safe-keeping of the jewels once in Switzerland.

On November 11 1918, coinciding with the armistice, Charles issued a proclamation in which he recognised the Austrian people’s right to determine their own form of state and “relinquish(ed) every participation in the administration of the State.”

Once the removal of the jewels became known, the scandal resulted in both the Italian government attempting to regain the former Medici prize jewel and the Austrian government openly debating the seizure of the Habsburg estate. The government seized all property formerly belonging to the Imperial Family and formally abolished all titles in 1919 and 1921, leading to the family heading into exile. However, once in exile in Madeira, Zita of Bourbon-Parma, wife to Charles, sought out Bruno Steiner at his Zürich residence on a trip into the country, finding the lawyer gone. Tracking him down to Frankfurt, Zita’s brother Xavier was allegedly assured that the jewels were safe and in a nearby bank. The trusting Xavier left and returned the next day to collect, only to once again find Steiner gone. All trace of both Steiner and the Florentine Diamond vanished into thin air despite Zita making an official complaint to police in Switzerland.

Hawera & Normanby Star, Volume XLVIII, Issue XLVIII, 22 November 1924

In 1923 Steiner was arrested in Paris and charged with the fraudulent disposal of the Austrian Crown Jewels, accused of selling the jewels to pawnbrokers instead of using them as collateral to obtain a loan. He was subsequently acquitted of all charges and told a very different side to the story. According to Steiner, the jewels were returned to the emperor when he entered Switzerland, and the truth was that Charles had sold the gems to fund his attempts to regain the throne, spending £80,000 on propaganda in a single year alone. The rest, Steiner alleged, had been sold by Maria Theresa with the emperor’s permission and a third portion went with him into exile in Madeira. Steiner was reported to have died in 1930 and officials at the Kunsthistorisches Museum in Vienna, the last confirmed location of the Florentine before 1918, stated in 1964 that they had no knowledge of the stone’s location.

Allegedly smuggled into South America, rumours have circulated for decades about the final destination of the world-famous diamond and its current whereabouts, with most experts believing the gem is likely to have been re-cut to disguise its provenance. One such rumour claims that the diamond came to the United States in the 1920s, and was subsequently cut up and resold into smaller diamonds that occasionally appear on the international diamond market. Rumours at the time even claimed that the Shah d’Iran diamond might have once been the Florentine.

In 1938 rumours circulated that Otto van Habsburg, last Crown Prince of Austria-Hungary, was to offer the Florentine for sale at the Amsterdam Diamond Exchange and by 1966, in a widely debunked book, Alphonse Sondheimer proclaimed that the diamond has been cut up into three pieces.

In 2006 the Encyclopaedia Britannia printed a theory that stated the diamond had never left Austria and remained in the country until the Second World War. At this time it was seized by the Nazis and hidden in a mine in Salzburg. Recovered by the United States 3rd army and General Mark Clark, the diamond was returned to Vienna. However, there is documented evidence that Charles I took the diamond with him into exile and officials of the Treasure Room in the Viennese Museum of Art state firmly that the diamond is not in their possession.

The most likely outcome is that the diamond was indeed re-cut and has already been located.

After an investigation by Gem Sleuth deduced that the diamond, if re-cut, had to have been round cut to avert a drastic reduction in weight, the company found only four light-yellow diamonds weighing over 70 carats to be known in this fashion. Eliminating three of the diamonds through provenance, only one remained as a suspect, a brilliant-cut light yellow diamond offered for sale by Christie’s at an exclusive Geneva hotel in November of 1981. Standing now at an exact 81.56 carats and framed with 15 small brilliants, the “unnamed yellow diamond” of auction lot 710 immediately raised speculation. Upon examining the stone, it showed clear evidence of being re-cut, and its former owner stated the diamond had initially had an unusual old-fashioned cut that had become out of style, leading to her father having the jewel reworked. The now-former owner claimed the diamond had been in her family since just after the First World War and the findings that this stone was the remains of the Florentine Diamond have been supported by diamond historian Lord Ian Balfour and De Beers.

I am a freelance long-form writer who writes on true crime, politics, history and more. I am entirely self-funded and if you liked this article, please consider a donation via Patreon as a token of appreciation or directly via PayPal. You can join my mailing list for the latest articles and also like my Facebook page. I’m also active on Twitter. I can be contacted for projects through my website MichaelEastWriter.com where you’ll also find lots more content.

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Michael East

Written by

Freelance writer. Writing on true crime, mysteries, politics, history, and more. | https://linktr.ee/MichaelEast

The Mystery Box

A publication about unsolved mysteries from the deep ocean to space and from antiquity to present day.

Michael East

Written by

Freelance writer. Writing on true crime, mysteries, politics, history, and more. | https://linktr.ee/MichaelEast

The Mystery Box

A publication about unsolved mysteries from the deep ocean to space and from antiquity to present day.

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