The desert rose is an aggregate of gypsum crystals that forms in particular climatic conditions. It is thus defined as the gypsum crystals arrange themselves to form the petals of a rose and because its formation is closely linked to arid and hot environments. For this mineral to form, at least two fundamental conditions are needed: the presence of a chalky evaporite deposit and an arid climate. In the evaporite deposit, located in the subsoil at a certain depth, water arrives, already present in the subsoil or rainwater, which dissolves (melts) the gypsum. The water, enriched with calcium sulphide present in the subsoil, tends to rise towards the surface due to the principle of capillarity. When it reaches the surface, due to the high temperatures, the water begins to evaporate, making the gypsum crystallize. Several cycles of rising water, with the subsequent evaporation, allow the growth of gypsum crystals up to decimetric dimensions.
Dimensions
Height (cm): 5-7
Depth (cm): 3-5
Width (cm): 9-10
Weight (g): 140-180
Property
Chemical Formula: CaSO4 (H2O) 2
Mohs scale: 2
Relative density: 2.3-2.4
Crystalline System: Monoclinic
