Cameo (carving)

Cameo (/ˈkæmioʊ/) is a method of carving an object such as an engraved gem, item of jewellery or vessel made in this manner. It nearly always features a raised (positive) relief image; contrast with intaglio, which has a negative image. Originally, and still in discussing historical work, cameo only referred to works where the relief image was of a contrasting colour to the background; this was achieved by carefully carving a piece of material with a flat plane where two contrasting colours met, removing all the first colour except for the image to leave a contrasting background.

Today the term may be used very loosely for objects with no colour contrast, and other, metaphorical, terms have developed, such as cameo appearance. This derives from another generalized meaning that has developed, the cameo as an image of a head in an oval frame in any medium, such as a photograph.

Ancient and Renaissance cameos were made from semi-precious gemstones, especially the various types of onyx and agate, and any other stones with a flat plane where two contrasting colours meet; these are "hardstone" cameos. In cheaper modern work, shell and glass are more common. Glass cameo vessels, such as the famous Portland Vase, were also developed by the Romans.

Modern cameos can be produced by setting a carved relief, such as a portrait, onto a background of a contrasting colour. This is called an assembled cameo. Alternatively, a cameo can be carved by the traditional, but far more difficult, method directly out of a material with integral layers or banding, such as (banded) agate or layered glass, where different layers have different colours.

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