LACLOCHE, Paris. Circa 1950. Ring in 950 platinum ‰ adorned at its center with a rare English-cut natural diamond weighing 13.44 cts in a double claw setting. Unsigned, hallmarked Helluin-Mattlinger. Small chips on the faceted and polished roundel and some edges. Gross weight: 8.7 g; TDD: 55. French Gemological Laboratory gemological report no. 409056 stating: - Color: I; Clarity: VS1; Fluorescence: none; Type: 1a; Mass: 13.44 cts. Expert: Emeric BUFFETAUD Viewing by appointment only, Friday May 10 and Monday May 13, 2024. A deposit will be required to bid on this lot, please contact the firm: 06 30 19 52 55 / [email protected] Live auctions will be closed for this lot. Although we can't be sure when this diamond was cut, as there would be little evidence to support it (traces of cutting from an old, poorly balanced material), this magnificent stone does give us some insight into the evolution of diamond cutting. There is in fact a small bound publication, in the form of a treatise on diamonds, in several editions, including that of 1753, by David Jeffries, an English diamond cutter and merchant. He himself translated this treatise into French (France was then the richest country in the world...). Jeffries dedicated his treatise to the Prince de Condé and, of course, to his magnificent pink diamond, still in Chantilly, acquired and donated by Louis XIII for the services rendered by the Grand Condé during the Thirty Years' War. What's interesting about this book is that it explains that the first brilliant cut, known as "brillant quarrée", arrived at the end of the 17th century, a good century before the creation of the Manufacture Royale de taille de diamants aux quinze-vingts in Paris by Louis XVI, revealed by Bleue-Marine Massard's thesis a few years ago; Jeffries explains that, in fact, they mainly cut roses, naïves, portraits and any opportunity to retain the maximum mass of the basic rough diamond, whose original shapes are multiple, depending on the category of the deposit (primary, secondary, etc.).At the time, it was a veritable obsession: the starting point was a rough diamond, for example two pyramids welded at the base: an octahedron with a starting mass. The aim was to cut it with as little weight loss as possible; cutting less saved time, less was broken and, ultimately, less was traded. For small stones and roses, they relied on the work of the "jouaillier" (jeweler), who set them to a high standard (cf. Moghul jewelry of the time), set silver spangles and so on. But around 1670, Tavernier understood that diamonds needed to be "brillianted" to improve their fire, i.e. geometrically adding small triangular facets inclined at a precise angle around the table; at the time, our 4Cs of today boiled down to the transparency and purity of the material. We speak of water: looking at a cut diamond can be compared to the sight of a small spring river. With a scale (1st water, 2nd water etc...), to which we may add the beauty of the hue: "They must look like a drop of perfectly clear rock water...". So we keep the octahedron's waistband (when it's an octahedron), polish it and "shine" the table after cleavage, as well as the breech, to shape what is then called the "quarré lustre". For us today, this quarried brilliant is an English cut, the famous "English cushion", the first regular "brilliant cut", that of the Regent, reported in 1698. The diamond we present today is an example of this cut. If you look closely at the photographs from the front, you can see obvious "wear" on the table edges, as if to testify to how long ago this stone was last set.