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Mahan

Topic:
Symmetry

domes

Curvature and diameter of a dome varies with its height. You can’t place the same number of congruent stars at every height. For this an ingenious technique was established that could be applied as well inside as outside of domes.
  • In the apex of the dome a star was placed, often12- or 16-pointed.
  • From apex to base the dome was divided into sectors of curved triangles, as many as the number of points of the stars at the apex. These curves triangles were used as unit repeat for the dome.
  • The curved triangles were filled in with stars, depending on the curvature of the dome. Doing so one could keep the segments on the stars constant and creating bigger and smaller stars.
  • On each row figures were created to connect the stars. The aim was to use as little different figures as possible and to avoid angles that distort the harmony of the dome.

Shah Ni'matllah Vali shrine Mahan (Iran - 1601)

The dome of the shrine was covered by blue, black and white ceramic tiles with a star pattern.
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In the picture below you can see the different stars following the curvature of the dome. Except on the row on top of the dome the different types of stars are connected by regular pentagons. At the base of the dome white lines suggest a horizontal tape. Higher they tend towards the apex.
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