Cluster of numerous gypsum “desert roses.” This material comes from just outside the town of Samalayuca, which lies approximately 80 km SSW of the crossing between Ciudad Juárez and El Paso, Texas.

Ex Wolfgang Schneider collection.

"Samalayuca is a small town on the Juarez-Chihuahua highway roughly 50 km south of El Paso-Juarez. The town's main claim to fame is a huge thermoelectric generator plant, visible from a long distance. South and east of the town lie the Samalayuca Dune Fields (Medanos) that feature star and barchan dunes up to 50m high. The sand comes from Laguna Guzman (aka Barreal Guzman) that lies just to the west. A popular site for filming used for "Dune" and "Conan the Destroyer".

Just north of the town, and less than 100m off the highway are old playa lake deposits where distinctive spherical aggregates of bladed tan-colored gypsum crystals ("desert roses"), often heavily included with sand, have been found. Specimens range from single balls up to 6 cm in diameter to clusters of intergrown balls weighing many tens of kilograms. Specimens have been mined in large quantities for many years and are a staple of rock shop inventory. The roses are often toasted with a blow torch to dehydrate the edges of the bladed crystals. This both hides damage to the edges and gives them a white edge that contrasts with the overall tan color of the gypsum."  mindat