Girih
Girih ("knot" in Persian) or gereh sazi in Persian ("knot making") is an Islamic decorative art form used in architecture and handicrafts (book covers, tapestry, small metal object), consisting of geometric lines that form an interlaced strapwork. In Iranian architecture, gereh sazi patterns were seen in banna'i brickwork, stucco and mosaic faience work.[1] Girih was defined "geometric (often star-and-polygon) designs composed upon or generated from arrays of points from which construction lines radiate and at which they intersect."[2]
In woodwork, gereh sazi can mean one of two different things. In one meaning, the geometric patterns create a latticework in which the space between the lines are either left as holes, or filled with wood, colored glass or other material. In another meaning, it can mean a tile panel made of polygons, stars or other geometric shapes; this was used to decorate mosques, palaces and private dwellings.
The three-dimensional equivalent of girih is called muqarnas. It is used to decorate the underside of domes or squinches.
History
Woodwork
In woodwork, the earliest surviving example of gereh sazeh is the balustrade of the Jumah Mosque in Nain, Iran. One of the earliest examples of a starts and polygon pattern is a minbar from 1369, originally from the Jumah Mosque of Bavanat, currently on display at the National Museum of Iran.
This woodwork technique was popular during the Safavid period, examples of it can be seen in various historic structures in Esfahan. In window screens, the gaps in the straps were filled with glass. In later periods, as this art form evolved, the gaps were no longer left with holes, the lines made thinner, and geometric patterns became denser and more complex. Girih patterns on ceilings were decorated with mosaic, paint and gild. In the Kajar period, the straight lines of girih became curved and were combined with vegetal patterns; mosaics included mirror pieces as well.[1]
Architecture
The earliest source mentioning girih as an architectural style is from 1565.[1] Pattern catalogs such as the Topkapi Scroll (late 15th century) were used by artisans.
Symmetric shapes are used in girih. 6-, 8- and 12- pointed stars were combined with various convex polygons. The lines that separated these shapes from each other were drawn as straps and often they were drawn as in an interlacing manner. These patterns had the potential of covering an infinite surface in a repeating manner. The oldest girih patterns had 2-, 3- and 6-fold rotational symmetry on a regular array of points.[1]
The predecessors of the girih style were seen in Byzantian Syria. The great mosque of Damascus had girih patterns on its window latices having 3-fold rotational symmetry. Later examples of girih seen in Iran were far more complex. In the 10th century, the gate of the Jurjir Mosque in Esfahan had multi-pointed geometric patterns. Fully developed girih patterns are not seen before the 11th century in Iran. Carved stucco panels with interlaced girih examples were discovered in Iran's Khorasan and Qazvin provinces.[1]
In the Seljuk, and later the Ilkhanid period, girih continued to be part of the architecutral repertory. In the 14th century girih became a minor player in the decorative arts and wes replaced by vegetal patterns during the Timurid era. However, geometrical strap work patterns continued to be an important element of decorative arts after the Timurid period.[1]
Construction
First girih patterns were made by copying a pattern template along a regular grid; the pattern was drawn with compass and straightedge. These patterns were like a two-dimensional two-dimensional crystal, tiling the plane with a unit cell. Because the tiling was done by translation or rotation operations, the unit cells had 2-, 3- , 4- or 6-fold rotational symmetry.
Girih patterns from around the year 1200, started having stars and polygon patterns having 5 and 10-fold rotational symmetry. Such figure can be drawn by compass and straightedge as well. However, some 15th century girih patterns had patterns that were not periodic anymore. Such patterns were constructed by the use of girih tiles. These were a set of five tiles with lines drawn on them; when used to tile the plane with no gaps, the lines form a girih pattern. It is not yet known when girih tiles were first used instead of compass and straighedge construction. The use of girih tiles on some buildings built around 1200 is considered likely.[3][4]
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Girih tiles. -
A girih pattern made from girih tiles. -
Detail from the Yeşil Mosque (Bursa, Turkey) made from the girih pattern on the left.
The girih patterns on the Darb-e Imam shrine built in 1453 at Esfahan had a much more complex pattern than previously seen. The details of the pattern indicates that girih tiles, rather than compass and straightedge, were used for decorating the shrine. The patterns on this shrine are aperiodic, that is, they do not form a regularly repeating pattern. Another characteristic of the patterns at the Darb-ı İmam shrine is that they are self-similar at different scales. The pattern that is discernible when the building is viewed from a distance occurs also in the detail pattern that one sees when near the building. Girih tilings possessed properties consistent with quasicrystalline tilings such as Penrose tilings predating them by five centuries.[3]
The Topkapi Scroll from the late 15th century documents that girih tiles were used to create girih patterns. The drawings in this pattern book shows the girih lines superimpose with the tiles used to generate the girih pattern.
Gallery
References
- ^ a b c d e f "Gereh Sazi". Encyclopaedia Iranica Online. Retrieved 2013-01-01.
- ^ Terry Allen (2004). "Islamic Art and the Argument from Academic Geometry". Retrieved 2012-01-23.
- ^ a b Peter J. Lu and Paul J. Steinhardt (2007). "Decagonal and Quasi-crystalline Tilings in Medieval Islamic Architecture" (PDF). Science. 315 (5815): 1106–1110. Bibcode:2007Sci...315.1106L. doi:10.1126/science.1135491. PMID 17322056.
- ^ Lu and Steinhardt, Supplementary figures