Cup of the Ptolemies in the context of "Cabinet des Médailles"

An engraved gem, frequently referred to as an intaglio, is a small and usually semi-precious gemstone that has been carved, in the Western tradition normally with images or inscriptions only on one face. The engraving of gemstones was a major luxury art form in the ancient world, and an important one in some later periods.

Strictly speaking, engraving means carving in intaglio (with the design cut into the flat background of the stone), but relief carvings (with the design projecting out of the background as in nearly all cameos) are also covered by the term. This article uses cameo in its strict sense, to denote a carving exploiting layers of differently coloured stone. The activity is also called gem carving and the artists gem-cutters. References to antique gems and intaglios in a jewellery context will almost always mean carved gems; when referring to monumental sculpture, the term counter-relief, meaning the same as intaglio, is more likely to be used. Vessels like the Cup of the Ptolemies and heads or figures carved in the round are also known as hardstone carvings.