16/09/2011

The history of gemstone carving

The terms intaglio and cameo are defined as carved gems with incised and raised engraving, respectively. The carving may be done either by simple manual tools or by rotary tools ( drilling and grinding ). The material for engraved gems is chiefly yielded by the minerals of the quartz group. Hematite was used for the ancient mid-eastern seal-cylinders. Engravings on emerald, beryl, garnet, peridot and topaz were rare. Through all ages glass offered a material for imitating, and substituting gems. For these glass-pastes a mold of an intaglio or a cameo was pressed in clay to cast the glass, which, after cooling, was brought into its final shape by refining with tools.
The oldest engravings on gems originated from about 5000 to 3000 B.C. The Hittites, Egytians , Assyrians, Persians and the ancient Greeks are worth mentioning for their art of carving gems. Remarkable works were accomplished by Greek artists for members of the Roman noble class during the time of early emperors. Famous examples are the Gemma Augustea ( Vienna ) and a sardonyx representing the triumph of Germanicus ( Paris ).
Seal-cylinder Gemma Augustea Engraved quartz ring with portrait of Marciana(?)
Since the time of Constantine the Great engravings on gems representing religious subjects were made in Byzantium. Our knowledge of ancient glyptograhpy is based on the collections of the important museums and on the abundance of gems in pieces of medieval jewelry. Although these gems are mostly pre-christian cameos re-used in christian objects.
Towards the middle of the 19th century a rapid decline of glytography began and the interest in carved gems was lost. Nowadays the noble art of glytography is mastered only by a small number of artists. A revival of glytography would certainly ad an element of special delicacy to the pictorial arts of today.
Resume of a text by Mister Heinz Goebbler, published in the " Zeitschrift der Deutschen Gesellschaft für Edelsteinkunde. Idar-Oberstein 1957 "
An interesting revival of this handcraft is on the way. Worldwide a growing number of very competent artists create astonishing engravings and gemstone sculptures.
Hubert Heldner   August 2001

Today, Idar-Oberstein is primarily known for the cutting of larger, more valuable gemstones, fantasy cuts (Fantasieschliffe), and the wholesale trade in polished gemstones (geschliffenen Edelsteinen). Every year around late September or early October, Idar-Oberstein is host to the Intergem trade show - short for the "International Trade Fair for Precious Stones and Jewellery."
There are several gemological research institutes [7] in Idar-Oberstein that include the 'German Foundation for Gemstone Research' (Deutsche Stiftung Edelsteinforschung - DSEF), Diamond Grading Laboratory (Diamant-PrŸflabor GmbH - DPL), German Association for Gemstone and Jewellery Evaluation (Deutsche Gesellschaft fŸr Edelsteinbewertung mbH - DEGEB), Research Institute for Gemstones and Precious Metals (Forschungsinstitut fŸr mineralische und metallische Werkstoffe, Edelsteine/Edelmetalle GmbH - FEE), and the German Gemmological Association (Deutsche Gemmologische Gesellschaft e.V. (DGemG).