Ulug Beg madrassa - muqarna
The main entrance of the Ulug Beg madrassa is crowned by a hugh arc. But above the actual gate a second arc is constructed with a muqarna construction in it.
The time of building the madrassa 1417-1420 can be situated between the these in Mizdakhan and Bukhara.
The 14th century muqarnas of Mizdakhan are of the type you often find in Turkey and Iran: Clear elements are arranged in layers leaning on the end of each other.
The 17e century muqarnas in Bukhara are designed as concentric circles around stars.
The transition between the layers is realised by connecting the points of the stars.
In between is the muqarna of the Ulug Beg madrassa:
The greater part of the rear side is flat. The transition to the half 24-ppointed star in the apex is realised in just a few layers. But below in boths corners is a 6-pointed star. The muqarna doesn't continue in layers of stars but evoluates in rather traditional layers of identifiable elements towards the top.
It's clear that you distinguish separate muqarna systems not only by region but also in time. And in Uzbekistan there's no rapture but an evolution from one system to another.
