The revival of the art of gem-engraving led to a large demand for cameos--themselves more suitable for decorative purposes than intaglios--as personal ornaments. "It was much the custom of that time," says Vasari, writing of the gem-engraver Matteo del Nassaro, "to wear cameos and other jewels of similar kind round the neck and in the cap." Matteo produced many admirable cameos for use as enseignes for Francis I and the nobles of his Court, almost every one of whom carried on their persons some example of his work. On jewels of this kind parts of the figures were occasionally executed in cameo, and the remainder in gold, chased and enamelled; but more frequently figures were worked entirely in hard material, and then, in accordance with the artistic taste of the time, enclosed in borders, enriched with enamel and jewel-work of the most exquisite variety of design. Unhappy vicissitudes, like those which the gems at Florence have undergone,[149] have in course of time despoiled many a cameo of its rich setting. Yet in the great public gem collections of London, Paris, Vienna, St. Petersburg, Berlin, Munich, and Dresden, as well as in the cabinets of private collectors, are to be found a number of beautiful examples of the jeweller's art at its best period, which have been preserved on account of the cameos they served to adorn. [149] In the night of December 17th, 1860, the Galleria delle Gemme of the Uffizi was entered by thieves, who carried off a large number of gems and jewels. Most of the gems were recovered, but nearly all robbed of their settings. All the jewels were lost (Gotti, A., _Le Gallerie di Firenze_, pp. 229 and 388). The finest enseigne that displays cameo and enamelled gold worked together in combination is Cellini's exquisite "Leda and the Swan," in the Münz-und-Antiken-Kabinet at Vienna. The head and the torso of the figure of Leda is in cameo--the latter being an antique fragment; the remainder of the jewel is of gold, enriched with enamels, diamonds, and rubies. This is considered to be the actual jewel executed by Cellini at Rome about 1524 for the Gonfalonier Gabriele Cesarini[150] (Pl. XXIX, 5). [150] Kenner (F.), _Cameen und Modelle des XVI. Jahrhunderts_, p. 27 (_Jahrbuch der Kunsthistor. Sammlungen des Kaiserhauses, IV_), 1886.