The Beau Sancy

(via Diamond Cuts in Historic Jewelry:1381-1910) Herbert Tillander writes:

The dominating feature of the Beau Sancy (documented 31 January 1589) is a central star composed of eight pentagonal facets round a very small octagonal table. Between the points of the stars are eight squares or lozenges, each divided into two triangles. Together, these twenty four facets form two large interlacing squares. The remaining thirty facets (eight lozenges and twenty-two triangles) all touch the girdle. The reverse side of the gem is almost an exact replica, as far as one can judge from an examination of the diamond in its setting. That means that there are 108 faces plus the table and culet. What an incredible masterpiece of precision and artistic inventiveness! The few small irregularities and inclusions do not in the least detract from its beauty.

The light effects of the Beau Sancy itself are wonderful. The facets on the reverse reflect brilliant rays of light through the front. It was given the name ‘Beau’ Sancy to distinguish it from the Grand Sancy, and it truly deserves its title. The measurements are:

Height: 22.4mm
Width: 19.5mm
Thickness: 11.5mm

It weight has been estimated at 33-34 ct, but I suggest that 35-36 ct would be nearer the truth.

It is documented that Queen Maria de’ Medici bought the Beau Sancy from Sancy himself. The transaction is dated 1604, and she is said to have paid ‘XXVm escus’ for it. For her coronation in 1610, the diamond was set at the top of the crown which she wears in her portrait. Maria died poverty-stricken and in exile, and her creditors disposed of any jewels she still possessed. The Beau Sancy was bought by Frederick Henry of Orange, and then passed to his descendants; it has never again been put up for sale. William III of Orange gave it to his bride, Mary, and after her death it went to Frederick, the future King of Prussia.

In the late 1960s, I knew that the Grand Sancy was in England, still at that time in the possession of the Astors. I also knew that the Beau Sancy had once formed part of te Prussian Crown Jewels. Through a series of chance meetings, I learned that Viscount Astor had deposited the head of the Hohenzollern family, Prince Louis Ferdinand of Prussia, grandson of William II, the last German Emperor. Having discovered the whereabouts of the two diamonds, I decided to try to reunite them—in Finland! There was already a Finnish connection: Paul Demidoff, who inherited the Grand Sancy in 1836, gave it as a wedding present to his bride Aurora Karamzin, a Finnish-born lady-in-waiting at the Russian court.

Years of preparatory work, correspondence and persuasions of the relevant authorities followed, until finally, in October 1972, Prince Louis Ferdinand himself came to Helsinki to open the exhibition ‘Two Historic Diamonds’. The two brothers, the Grand Sancy and the Beau Sancy, were reunited after a separation of some 370 years.