Most of Petra monuments were carved in two layers of sandstone. These layers are referred to as “Disi Sandstone”, in the upper parts of the site, and “Umm Ishrin sandstone” below it.

The ancient city of Petra is carved almost entirely from kaleidoscopic quartz sandstone, which was deposited during the Cambrian and Ordovician periods. The two primary types of stone are the Umm Ishrine Sandstone, which provides the vibrant "rose-red" and orange hues seen on the famous Treasury (Al-Khazneh), and the Disi Sandstone, which is a paler grey or white. What makes Petra's stone truly special are the intricate "Liesegang rings"—natural, swirl-like patterns of iron and manganese oxides that create streaks of red, ochre, purple, and blue within the rock. This is most famously visible in the Silk Tomb, where the ceiling and walls look like draped fabric or abstract paintings. The stone is relatively soft, which allowed the Nabataeans to carve such intricate facades using only hand tools, but it is also highly susceptible to erosion from wind and flash floods. In 2026, conservationists are using advanced nanotechnology "consolidants" to help strengthen these porous stones without changing their iconic colors, ensuring that the "Rose City" survives for future generations.