Guillaume Glorieux is Director of Education and Research at L’Ecole des Arts Joailliers. He was professor of modern art history at the University of Rennes 2-Haute Bretagne. He is notably the author of Watteau (CItadelles and Mazenod, 2011) and Les Arts joailliers: Métiers d´excellence, Gallimard, 2019. Michael Decrossas holds a doctorate from the Ecole Pratique des Hautes Études. He has notably participated in the book Ornements. XIVe-XIXe siècles. Chefs d’oeuvres de la Bibliothèque de l’INHA, Jacques Doucet collections, Paris, Mare & Martin / INHA editions, 2014 Stéphanie Desvaux is an archivist, specializing in the promotion of patrimony.