A gemstone decorated with a carved or engraved design, monogram, portrait or inscription, incised as an intaglio or in relief as a cameo.
The stones most frequently so used were the agate and sardonyx, which could be carved in a two-colour effect, but some diamonds bear engraved names, dates, and inscriptions (remarkable in view of their hardness and the primitive tools available at the time), e.g. the Shah diamond, the Akbar Shah diamond, the Darya-I-Nur (Iran) diamond, and the Jahangir diamond, and some rubies and emeralds were also engraved.
The work was done originally with a bow-drill, and later on a grinding wheel with the stone, attached to a dop-stick, held against it; a modern process uses a revolving burr. The early process was used from ancient times in Mesopotamia, mainly for design in intaglio on a seal; later in Greece, in the Hellenistic period, gems were cut as a cameo to be worn ornamentally. The process was much used in Egypt for making scarabs and in Minoan, Myceneaen, Greek, Etruscan, and Roman jewelry, especially for cameos and intaglios depicting persons and mythological characters.
It was popular again in the Middle Ages when many of the cameos were thought to have amuletic powers. During the Renaissance engraved gemstones were made with original designs well as copying the classical examples. Such engraved gemstones continued to be popular in the 17th and 18th centuries; among leading Continental engravers of the 18th century were the Italian Johann Anton Pichler, the French Jacques Quay, and the German Johann Lorenz Natter.
Leading English engravers of gemstones were Edward Burch (1730-1814) and his pupil Nathanel Marchant (1739-1816), who depicted classical and contemporary subjects; others also produced accurate copies of ancient gems, but forgers, notably Thomas Jenkins in Rome, made cheap imitations.
Important collections of engraved gemstones were assembled by Pope Paul II (1417-71) and at the courts of the Gonzaga, the Este, and the Medici (some made for Lorenzo de’ Medici are inscribed with an abbreviation of his name, Lau.R.Med.) and also in England, e.g. by Thomas Howard, Earl of Arundel (1585-1646) and the 2nd Duke of Devonshire.
Imitations of cameos and intaglios were made in Jasper Eartenware by Wedgwood and in paste by James Tassie.
Important engraved gemstones have been set in jewelry in recent years, e.g. the emeralds in the Farah Diba Crown. Some of the gem-engravers of antiquity are identified by their mark. Many engraved gemstones are too large to be worn as jewelry and were made as ornaments for a gem cabinet; for this reason such examples (e.g. the Gemma Augustea) are beyond the scope of this site.