Relief

Low relief or bas-relief

A low relief is a projecting image with a shallow overall depth, for example used on coins, on which all images are in low relief. In the lowest reliefs the relative depth of the elements shown is completely distorted, and if seen from the side the image makes no sense, but from the front the small variations in depth register as a three-dimensional image. Other versions distort depth much less. The term comes from the Italian basso rilievo via the French bas-relief (French pronunciation: [baʁəljɛf]), both meaning "low relief". The former is now a very old-fashioned term in English, and the latter term is becoming so.

Low relief is a technique which requires less work than high relief, and is therefore cheaper to produce, as less of the background needs to be removed in a carving, or less modelling is required. In the art of Ancient Egypt, Assyrian palace reliefs, and other ancient Near Eastern and Asian cultures, a consistent very low relief was commonly used for the whole composition. These images would usually be painted after carving, which helped define the forms; today the paint has worn off in the great majority of surviving examples, but minute, invisible remains of paint can usually be discovered through chemical means.

The Ishtar Gate of Babylon, now in Berlin, has low reliefs of large animals formed from moulded bricks, glazed in colour. Plaster, which made the technique far easier, was widely used in Egypt and the Near East from antiquity into Islamic times (latterly for architectural decoration, as at the Alhambra), Rome, and Europe from at least the Renaissance, as well as probably elsewhere. However, it needs very good conditions to survive long in unmaintained buildings – Roman decorative plasterwork is mainly known from Pompeii and other sites buried by ash from Mount Vesuvius. Low relief was relatively rare in Western medieval art, but may be found, for example in wooden figures or scenes on the insides of the folding wings of multi-panel altarpieces.

The revival of low relief, which was seen as a classical style, begins early in the Renaissance; the Tempio Malatestiano in Rimini, a pioneering classicist building, designed by Leon Battista Alberti around 1450, uses low reliefs by Agostino di Duccio inside and on the external walls. Since the Renaissance plaster has been very widely used for indoor ornamental work such as cornices and ceilings, but in the 16th century it was used for large figures (many also using high relief) at the Chateau of Fontainebleau, which were imitated more crudely elsewhere, for example in the Elizabethan Hardwick Hall.

Shallow-relief, in Italian rilievo stiacciato or rilievo schicciato ("squashed relief"), is a very shallow relief, which merges into engraving in places, and can be hard to read in photographs. It is often used for the background areas of compositions with the main elements in low-relief, but its use over a whole (usually rather small) piece was effectively invented and perfected by the Italian Renaissance sculptor Donatello.^[7][8]

In later Western art, until a 20th-century revival, low relief was used mostly for smaller works or combined with higher relief to convey a sense of distance, or to give depth to the composition, especially for scenes with many figures and a landscape or architectural background, in the same way that lighter colours are used for the same purpose in painting. Thus figures in the foreground are sculpted in high-relief, those in the background in low-relief. Low relief may use any medium or technique of sculpture, stone carving and metal casting being most common. Large architectural compositions all in low relief saw a revival in the 20th century, being popular on buildings in Art Deco and related styles, which borrowed from the ancient low reliefs now available in museums.^[9] Some sculptors, including Eric Gill, have adopted the "squashed" depth of low relief in works that are actually free-standing.

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  "Blocked-out" unfinished low relief of Ahkenaten and Nefertiti; unfinished Greek and Persian high-reliefs show the same method of beginning a work.
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  Persian low or bas-relief in Persepolis – a symbol of Zoroastrian Nowruz – at the spring equinox the power of the bull (personifying Earth) and lion (personifying the Sun) are equal.
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  Assyrian low relief, Lion Hunt of Ashurbanipal, North Palace, Nineveh
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  Atropos cutting the thread of life. Modern Greek low relief.
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  Donatello's rilievo stiacciato or shallow relief of the "Assumption of the Virgin" on a tomb, 1420s
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  Soviet bas-relief

Mid-relief

Mid-relief, "half-relief" or mezzo-rilievo is somewhat imprecisely defined,^[10] and the term is not often used in English, the works usually being described as low relief instead. The typical traditional definition is that about half of the subject projects,^[11] and no elements are undercut or fully disengaged from the background field. The depth of the elements shown is normally somewhat distorted.^[12]

Mid-relief is probably the most common type of relief found in the Hindu and Buddhist art of India and Southeast Asia. The low to mid-reliefs of 2nd-century BCE to 6th-century CE Ajanta Caves and 5th- to 10th-century Ellora Caves in India are rock reliefs. Most of these reliefs are used to narrate sacred scriptures, such as the 1,460 panels of the 9th-century Borobudur temple in Central Java, Indonesia, narrating the Jataka tales or lives of the Buddha. Other examples are low reliefs narrating the Ramayana Hindu epic in Prambanan temple, also in Java, in Cambodia, the temples of Angkor, with scenes including the Samudra manthan or "Churning the Ocean of Milk" at the 12th-century Angkor Wat, and reliefs of apsaras. At Bayon temple in Angkor Thom there are scenes of daily life in the Khmer Empire.

High relief

High relief (or altorilievo, from Italian) is where in general more than half the mass of the sculpted figure projects from the background. Indeed, the most prominent elements of the composition, especially heads and limbs, are often completely undercut, detaching them from the field. The parts of the subject that are seen are normally depicted at their full depth, unlike low relief where the elements seen are "squashed" flatter. High relief thus uses essentially the same style and techniques as free-standing sculpture, and in the case of a single figure gives largely the same view as a person standing directly in front of a free-standing statue would have. All cultures and periods in which large sculptures were created used this technique in monumental sculpture and architecture.

Most of the many grand figure reliefs in Ancient Greek sculpture used a very "high" version of high relief, with elements often fully free of the background, and parts of figures crossing over each other to indicate depth. The metopes of the Parthenon have largely lost their fully rounded elements, except for heads, showing the advantages of relief in terms of durability. High relief has remained the dominant form for reliefs with figures in Western sculpture, also being common in Indian temple sculpture. Smaller Greek sculptures such as private tombs, and smaller decorative areas such as friezes on large buildings, more often used low relief.

Hellenistic and Roman sarcophagus reliefs were cut with a drill rather than chisels, enabling and encouraging compositions extremely crowded with figures, like the Ludovisi Battle sarcophagus (250–260 CE). These are also seen in the enormous strips of reliefs that wound around Roman triumphal columns. The sarcophagi in particular exerted a huge influence on later Western sculpture. The European Middle Ages tended to use high relief for all purposes in stone, though like Ancient Roman sculpture, their reliefs were typically not as high as in Ancient Greece.^[13] Very high relief re-emerged in the Renaissance, and was especially used in wall-mounted funerary art and later on Neoclassical pediments and public monuments.

In the Buddhist and Hindu art of India and Southeast Asia, high relief can also be found, although it is not as common as low to mid-reliefs. Famous examples of Indian high reliefs can be found at the Khajuraho temples, with voluptuous, twisting figures that often illustrate the erotic Kamasutra positions. In the 9th-century Prambanan temple, Central Java, high reliefs of Lokapala devatas, the guardians of deities of the directions, are found.

The largest high relief sculpture in the world is the Stone Mountain Confederate Memorial in the U.S. state of Georgia, which was cut 42 feet deep into the mountain,^[14] and measures 90 feet in height, 190 feet in width,^[15] and lies 400 feet above the ground.^[16]

Sunk relief

Sunk or sunken relief is largely restricted to the art of Ancient Egypt where it is very common, becoming after the Amarna period of Ahkenaten the dominant type used, as opposed to low relief. It had been used earlier, but mainly for large reliefs on external walls, and for hieroglyphs and cartouches. The image is made by cutting the relief sculpture itself into a flat surface to enhance the impression of three-dimensionality.^[17] In a simpler form, the images are usually mostly linear in nature, like hieroglyphs, but in most cases the figure itself is in low relief, but set within a sunken area shaped round the image, so that the relief never rises beyond the original flat surface. In some cases the figures and other elements are in a very low relief that does not rise to the original surface, but others are modeled more fully, with some areas rising to the original surface. This method minimizes the work removing the background, while allowing normal relief modelling.

The technique is most successful with strong sunlight to emphasise the outlines and forms by shadow, as no attempt was made to soften the edge of the sunk area, leaving a face at a right-angle to the surface all around it. Some reliefs, especially funerary monuments with heads or busts from ancient Rome and later Western art, leave a "frame" at the original level around the edge of the relief, or place a head in a hemispherical recess in the block (see Roman example in gallery). Though essentially very similar to Egyptian sunk relief, but with a background space at the lower level around the figure, the term would not normally be used of such works.

It is also used for carving letters (typically om mani padme hum) in the mani stones of Tibetan Buddhism.

Counter-relief

Sunk relief technique is not to be confused with "counter-relief" or intaglio as seen on engraved gem seals – where an image is fully modeled in a "negative" manner. The image goes into the surface, so that when impressed on wax it gives an impression in normal relief. However many engraved gems were carved in cameo or normal relief.

A few very late Hellenistic monumental carvings in Egypt use full "negative" modelling as though on a gem seal, perhaps as sculptors trained in the Greek tradition attempted to use traditional Egyptian conventions.^[18]

Small objects

Small-scale reliefs have been carved in various materials, notably ivory, wood, and wax. Reliefs are often found in decorative arts such as ceramics and metalwork; these are less often described as "reliefs" than as "in relief". Small bronze reliefs are often in the form of "plaques" or plaquettes, which may be set in furniture or framed, or just kept as they are, a popular form for European collectors, especially in the Renaissance.

Various modelling techniques are used, such repoussé ("pushed-back") in metalwork, where a thin metal plate is shaped from behind using various metal or wood punches, producing a relief image. Casting has also been widely used in bronze and other metals. Casting and repoussé are often used in concert in to speed up production and add greater detail to the final relief. In stone, as well as engraved gems, larger hardstone carvings in semi-precious stones have been highly prestigious since ancient times in many Eurasian cultures. Reliefs in wax were produced at least from the Renaissance.

Carved ivory reliefs have been used since ancient times, and because the material, though expensive, cannot usually be reused, they have a relatively high survival rate, and for example consular diptychs represent a large proportion of the survivals of portable secular art from Late Antiquity. In the Gothic period the carving of ivory reliefs became a considerable luxury industry in Paris and other centres. As well as small diptychs and triptychs with densely packed religious scenes, usually from the New Testament, secular objects, usually in a lower relief, were also produced.

These were often round mirror-cases, combs, handles, and other small items, but included a few larger caskets like the Casket with Scenes of Romances (Walters 71264) in Baltimore, Maryland, in the United States. Originally they were very often painted in bright colours. Reliefs can be impressed by stamps onto clay, or the clay pressed into a mould bearing the design, as was usual with the mass-produced terra sigillata of Ancient Roman pottery. Decorative reliefs in plaster or stucco may be much larger; this form of architectural decoration is found in many styles of interiors in the post-Renaissance West, and in Islamic architecture.