In the 1870s, Edward VII, then the Prince of Wales, ordered from Hancocks London a custom necklace for his mistress Lillie Langtry, the actress and legendary beauty of her day. Appropriately, Langtry later wore the elaborate gold, turquoise and coral piece, featuring winged scarabs in the then-fashionable Egyptian Revivalist style, for the opening night of her starring role in Antony and…