Mardin is one material. Midyat limestone comes out of the ground soft enough to cut with a hand chisel and hardens in the open air, so the entire city — madrasa, monastery, merchant house — is carved rather than assembled.

The town steps down a hillside above the Mesopotamian plain, each roof serving as the terrace of the house above. This system takes that literally: stacked horizontal bands, cut edges, hard cast shadows, and ornament that exists as depth in the surface rather than colour on top of it.