Cooper Hewitt says...

From Hancocks of London:
From the start Dusausoy sold both jewellery by their own design, and antiques. 1889 The Dusausoy mark was registered by Mrs. Dusausoy, it included the initials ‘PD’ and a symbol of two stars. It was registered at the Rue Beaurepaire. 1905 Dusausoy began to deal gemstones. 1912 Mme Dusausoy’s son, Justin, registered his own mark in April, the initials ‘JD’ with a diamond shape. They advertised the valuation, modification and improvement of antique pieces, and specialised in re-mounting old stones at their 41, Boulevard des Capucines workshop in Paris. Justin was assisted by his son who managed some of the business dealings and also designed some pieces. Pierre, Jean’s brother also came to become a director. 1922 Dusausoy exhibited at the ‘Salons des Industries d’Art’ at the Musee des Arts Decoratifs in the Louvre. 1925 They exhibited again some remarkable jewellery at the ‘Exposition des Arts Décoratifs’ in Paris, among such names as Fouquet, Van Cleef and Arpels, Aucoc, Chaumet and Marchak. Madelaine Chazel contributed to the collection which caught the eye of the chairman of the committee at the time, the George Fouquet. He was enthusiastic about the firm, saying they were ‘one of the most interesting in the French section…showing beautiful stones…in combinations of lines ingeniously arranged’. The collection included the ‘Stalactite’ bracelet, the Maison Dusausoy were awarded a Gran Prix. The firm made an opal brooch for the exhibition – a modern looking jardinière brooch centralising an oval opal which was surrounded by geometric-petalled cabochon ruby centred flowers. 1927-28 The firm travelled to Madrid, Rotterdam and Athens to showcase their collection. 1929 Justin travelled to Cairo to judge the ‘Exposition Francaise’. He made the most of it to exhibit a parure made up of a bracelet, pendant and ring, which were made up of onyx, platinum, all in geometric compositions. The same year, the Musee Galliera held a jewellery exhibition and the Dusausoy brothers worked alongside Henri Vever to create a retrospective of ‘The Women’s parures 100 Years ago'. Amongst the pieces exhibited by Dausausoy was a pendant consisting of baguette and rose-cut diamond cascade with black onyx ‘shadows’ on a thin rigid chain. The exhibition was a milestone establishing bold and advancing new jewellers. Some other pieces by the firm consisted of graduating natural peal brooches with cabochon emeralds held by abstracted diamond pave motifs. 1935 Dusausoy created jewellery which had a great deal of aesthetic versatility. A purchase would come in a large taupe-brown velvet box with supports for just four clips which one could wear in up to 30 given combinations, as a tiara, bracelets, or different brooch compositions with the emphasis on the geometric lines inspired by cubism and very reminiscent of the Raymond Templier style. Andy Warhol purchased a set, which are extremely rare and very rarely seen due to the limited quantity of sets produced. 1937 The Maison Dusausoy exhibited at the ‘Exposition Internationale’ in Paris. 1939 During the Second World War the firm seemed to concentrate on antique valuations and trade. 1948 Janine Lacroix appears advertising Dusausoy jewellery 1970 The firm ceased trading.