Unseen by the public for two centuries, Marie Antoinette’s diamonds and pearls went under Sotheby’s hammer as part of one of the most important royal jewellery collections ever to come to auction. The auction took place in the Swiss city of Geneva on Thursday 15 November and, out of more than 100 lots, included 10 breathtaking treasures that belonged to the ill-fated Queen of France. The major collection—held by the Italian royal House of Bourbon-Parma...