[167] See note, p. 235. The tendency of placing the stone in a very high bezel was a tradition from the Middle Ages, where a preference had always been shown for the stone being so set. The ornamental rings of the Renaissance followed a uniform outline as far as their bezels and settings were concerned. They contained, as a rule, one stone only, backed by a foil or _paillon_, and set in a box-like collet, square and pyramidal, and closed behind. The gold was rubbed over the setting edge of the stone, and the four side surfaces then decorated in a variety of ways by the application of enamel, and sometimes overlaid with an additional ornamentation in imitation of claws. The stone itself, usually table-cut, was frequently a ruby. [Illustration: Triple rings set with pointed diamonds. Device of Cosimo de' Medici. (Figured in Botticelli's "Pallas" in the Pitti Gallery.)] One peculiar variety of ring, known from the early part of the fifteenth century, is deserving of note. Its design was founded upon the natural octahedrite shape of the diamond, and was distinguished by a very high bezel, which received one half of the octahedron and allowed the other to project upwards. Rings set thus with pointed diamonds were in high favour until the middle of the seventeenth century, and were employed for writing upon glass--a practice which appears to have been much in vogue. The most characteristic examples of the _diamante in punta_ were those adopted by the Medici as their device. Three diamond rings interlaced were employed by Cosimo (d. 1464); Piero took one diamond ring held in the claw of a falcon; Lorenzo continued the device of the ring, in which he placed three feathers. The best-known representations of these three devices are figured in Paolo Giovio's _Dialogo dell' imprese_. In addition to the case for the stone, the sides or "shoulders" of the ring which held it were the subject of special artistic development. They took the form of small figures, winged creature, masks, and other ornaments in relief and richly enamelled; while for smooth surfaces champlevé enamel was employed in a variety of designs. So extraordinarily elaborate is the work on some of these rings that it would almost seem as if they were produced rather as examples of the skill of the craftsman than as objects for actual use.