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Kharraqan 2

The western tower is built in 1093 by the same architect, 25 years later than the first one. Where the oldest bears 30 patterns, the western tower bears as much as 70 patterns. Remarkable is the complicated multi- interpretable tympan.
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Pentagons are apparent. They are arranged in quartets, defining squares. But one can define different grids and unit repeats.
  • You can define a square grid and a tiling created by glide mirroring.
  • Following lines in clay a hexagonal grid can be defined.
  • When rotating these hexagons by 90° they define, superposed with the original ons a grid of equal irregular pentagons.
  • This last grid can be read too as a grid of 8-pointed bow ties.
According to Carol Bier the ambiguity and complexity of these patterns point towards the later Gonbad-e Kabud as a continuous experiment and an evolution of mathematical insight. Looking only at this one monument in Maragha as an isolated building doesn’t bring justice to history. These buildings clearly show a sophisticated understanding of angles, lines, numbers and forms in the plane and a recognition of what we now call tilings and symmetries.
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