Rock relief

A rock relief or rock-cut relief is a relief sculpture carved on solid or "living rock" such as a cliff, rather than a detached piece of stone. They are a category of rock art, and sometimes found in conjunction with rock-cut architecture. However, they tend to be omitted in most works on rock art, which concentrate on engravings and paintings by prehistoric peoples. A few such works exploit the natural contours of the rock and use them to define an image, but they do not amount to man-made reliefs. Rock reliefs have been made in many cultures, and were especially important in the art of the Ancient Near East. Rock reliefs are generally fairly large, as they need to be in order to have an impact in the open air. Most of those discussed here have figures that are over life-size, and in many the figures are multiples of life-size.

Stylistically they normally relate to other types of sculpture from the culture and period concerned, and except for Hittite and Persian examples they are generally discussed as part of that wider subject. The vertical relief is most common, but reliefs on essentially horizontal surfaces are also found. The term typically excludes relief carvings inside caves, whether natural or themselves man-made, which are especially found in India. Natural rock formations made into statues or other sculpture in the round, most famously at the Great Sphinx of Giza, are also usually excluded. Reliefs on large boulders left in their natural location, like the Hittite İmamkullu relief, are likely to be included, but smaller boulders may be called stelae or carved orthostats. Many or most ancient reliefs were probably originally painted, over a layer of plaster; in some traces of this remain.

The first requirement for a rock relief is a suitable face of stone; a near vertical cliff minimizes the work required. Most of the ancient Near East was well supplied with hills and mountains offering many cliff faces. An exception was the land of Sumer, where all stone had to be imported over considerable distances, and so the art of Mesopotamia only features rock relief around the edges of the region. The Hittites and ancient Persians were the most prolific makers of rock reliefs in the Near East.

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