Bibi Khanum mosque - S-wheel pattern - ks
In the S-shapes you can read Alahu akbar (God is great).
Central in the square you can read the name of Ali, foor sunits the 4th calif, for sjiits the first of the 12 Imams.
The patters is created by overlapping squares forming a rectangle. Together with an overlapping identic rectangle it forms an S-shapes arranged around a central square.