GEMME. — The use of gems, especially in rings, was very common in the Roman world, and fashion ensured that it continued among Christians as well; Tertullian, in fact, mocked women who “wore bags of gold on each of their fingers” (De cultu feminarum, 9: PL 1, 1314).
The gems could bear mythological scenes, engraved or in relief. Clement of Alexandria admonishes: “Among Christians we may have one ring for sealing and closing valuable objects more securely; all other rings are not permitted to us. The images engraved upon them for use as seals should preferably be a dove, a fish, or a swift ship under full sail; one may also represent a lyre, like Polycrates, or an anchor, like Seleucus, and finally a fisherman on the seashore, whose sight will remind us of Peter and Moses. But one must beware of putting on one’s finger images of idols, the mere thought of which is a crime. Neither sword, nor bow, nor arrow, nor vessels that recall the orgies to those devoted to temperance.” And he adds: “If the faithful adopted the sign of the cross or scenes from other mysteries of the Christian faith, they risked betraying themselves before the pagans; if, on the other hand, they placed profane and voluptuous subjects on their rings, they ran the danger of offending God” (Paedagog.: PG 8, 629 and 633).
In the Christian cemeteries, especially during the plundering carried out there in the seventeenth and eighteenth centuries, very many gems found inserted in the sealing mortar of the tombs were removed. Boldetti speaks of “jaspers, topazes, plasma, and especially intaglios in sapphire agate and cameos of various kinds” discovered in his day (Osservazioni sopra i cimiteri dei SS. Martiri, Roma 1720, pp. 495-96); many of them entered the collection of Cardinal Carpegna.
In 1861, a carnelian was extracted from the cemetery of Callistus, at the third milestone of the Via Aurelia, later called that of Calepodius, on which the triumph of Bacchus was represented; Boldetti reports as having come from the cemetery of Priscilla a cameo with the head of Augustus; a cameo with Ganymede is said to have been found in the cemetery “in catacumbas.” Boldetti reproduced ten rings found in the underground cemeteries of Rome, bearing symbols of the anchor and the ship, with the monogram isolated or with the A and the E between two palms (op. cit., pp. 502 and 506); Carrucci reproduced others, bearing the symbols of the Good Shepherd, the ΙΧΟΤΕ of the fisherman, the dolphin clinging to the anchor, Jonah, Daniel, etc. (Storia dell’arte cristiana, VI, Prato 1880, tavv. 477-78).
In 1851 G. B. De Rossi found in the major cemetery on the Via Nomentana a fragment of Eastern sardonyx bearing the head of Augustus, now in the Christian Museum of the Vatican Library; in the same cemetery he saw embedded in the mortar of a loculus a chalcedony phalera, of the type of those already seen by Buonarroti and which Borghesi demonstrated had been worn sewn onto the chest and on belts, especially military ones.