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 ). 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).

Idar-Oberstein the city of gemstone carvers.

Gem carving tecniques

Gem Carving: Materials and Techniques

Semi precious hard stones such as carnelian, chalcedony, amethyst, and agate have long been carved with decorative and figural designs. Intaglios As early as 5000 B.C., craftsmen in Mesopotamia used hand-powered tools to engrave images into stone blanks, creating intaglios (so called from the Italian intagliare, "to cut into"). Similar methods were employed by ancient artisans in Egypt, Greece, Rome, and Etruria. Intaglios were used to make relief impressions when pressed into wax, clay, or another sealing material. Cameos Around 250 B.C. a new carving technique developed: by cutting away the area surrounding a figure, artisans formed relief images known as cameos. The different hues of banded stones were exploited to enhance the appearance of depth with multicolored compositions.		. .

Cameos are created by carving into a top (often white)layer of stone to reveal the colored band underneath An intaglio (top) is cut below the surface of a gemstone, while a cameo (bottom) is carved in relief Carving Tools Although intaglios are concave and cameos are convex, both are produced in a similar fashion. A cutting tool dipped in a slurry of abrasive powder and oil is turned while a gemstone is manipulated against it. Cutters of different shapes and materials can be used—drills, wheels, cones, and balls made of copper, bronze, iron, or something softer such as wood or even reed. It is the powder (emery or corundum in antiquity, diamond dust today) carried by the tool, not the tool itself, that actually carves the stone. This engraving depicts an 18th-century carver along with a variety of cutting tools. The instruments used by ancient carvers were similar, being turned by a bow rather than a foot pedal. Image top right: Hermaphroditus Seated on an Altar (detail), possibly by Protarchos, 150–100 B.C. Sardonyx cameo set in a modern gold ring. The J. Paul Getty Museum, 2001.28.9