Desert rose

In the appearance of the living and the inanimate world, despite their differences in nature, we can observe many common features. This recognition is reflected in the fact that certain varieties of minerals and rocks of special shape formed on other parts of the earth’s surface are called flowers, plants or animals in their names: miniature flower, iron blossom, sulfur blossom, mossach, roses of Incas, rose quartz, carnations, tiger eyes, falcon eyes, etc. In the past, it was often believed that these branch-boogle crystal miracles, needle bouquets and silky-light color harmonies were the fossil remains of the wildlife, and they wore interesting phrases and legends. Under the climatic conditions of the deserts, the fossilized, rose-like mineral formations of desert roses form in a sandy environment near the surface. Their raw material consists of barite (barium sulphate) or rosette (water-containing calcium sulphate) and, for which they have been awarded the desert flag, they cover sand. Desert roses formed from gypsum in North African sandstones are specimens in which the dissolved calcium sulphate content of the groundwater near the surface is partially precipitated by the evaporation of water and partly incorporated into the crystal lattice of the new mineral formed. Meanwhile, the sand grains accumulate. The color of the dull, opaque formations depends on the color of the gypsum as the binder and on the sand particles in it, as well as on further dirt. For example, if they also contain iron oxide, they often color the crystals to yellowish-brown or light brown. The binder of the desert rose is soft, so it is easily damaged and its scratching surface is white. (Source: László Varga, Life and Science 1999/12)