Martian regolith is a loose crustal coating created by weathering and blown everywhere by wind. Minerals from volcanic basalt are the main components, primarily olivine (magnesium, iron, and silicon), pyroxene (calcium, magnesium, and iron), and feldspar (calcium, aluminum, silicon, and sodium).
The regolith also contains perchlorate salts, formed by the action of ultraviolet radiation on Martian dust lofted into the atmosphere. Perchlorates interfere with the thyroid by blocking iodine uptake, leading to fatigue, cognitive effects, and metabolic problems. Regolith must be rinsed with water or strongly heated to remove them. Once cleaned, it can be fortified with waste from organisms and balanced with nutrients to produce usable soil.