Perseus and Andromeda (recto); Venus and Adonis (verso)

This oval of lapis lazuli is only about two millimetres thick, and it is painted on both faces. On this side Andromeda stands chained to a rock while Perseus swoops down on the sea monster, riding the winged horse Pegasus, and the flecked blue stone serves as sky and sea at once. Turn it over and Venus finds Adonis killed by the boar. The Borghese inventory of 1693 lists the piece without an author. Later inventories credited the Renaissance painter Giulio Romano, then the Florentine Passignano, and only in 1812 Tempesta. In 1833 the family bound its collection by an entail, a legal tie meant to keep it together, and this little oval was left outside it, so it stayed with the heirs. The Italian State bought it from them in 2005, and it is now shown in Room 19.