Desert rose crystal discovered in Umm Bab
Shaping the Qatar Peninsula (Quaternary)
Object Name: Desert Rose Crystal
Period: Shaping the Qatar Peninsula (Quaternary)
Date: 2 million – 4,000 years ago
Dimensions: 190 mm (H) x 710 mm (W) x 760 mm (D) 40 kg (Wt)
Medium: gypsum
Registration Number: QNM.2012.934.1
Place Of Discovery/Findspot:  Umm Bab
This irregular diamond-shaped object with a relatively flat base is a large, grey desert rose made up of naturally formed gypsum crystals. Desert roses are created through a process involving gypsum formation below the surface of coastal or inland sabkhas. Due to extremely high evaporation rates, sabkha groundwater reaches salinity levels that exceed the concentration of seawater, causing gypsum, a calcium sulfate mineral, to precipitate and form desert roses. The color of desert roses varies depending on the sediment incorporated into the crystal structure. Desert roses are a common feature found in Qatar's coastal and inland sabkhas, particularly at Khor Al-Adaid and Dukhan.
During the Quaternary period, Qatar Peninsula got its shape. The waters of the Gulf rose and fell as glaciers retreated and advanced across the world. Sea levels stabilised around 4,000 years ago, defining the coastline of Qatar as we know it today.
Umm Bab