The heart of Anna Lopukhina, royal mistress to the Emperor of Russia, turned to ice after his assassination in 1801 and, it was said, on her subsequent death at 27, cut into a gem by the Winter Palace's royal jeweller.An intricate, antiqued polished pewter, 18th century Baroque-style choker set with a large, Swarovski black diamond crystal at its centre, and two small white crystals either side and a black crystal dropper beneath.//On doubled, 38"/96 cm long, 24 mm wide black satin ribbons, for hand tying.