ИСТИНА

Ferrihydrite, an iron oxide hydroxide, is a much widespread material. It enters, as a constituent, in various bands of environments, such as clays and soils, soluble fraction of weathered rocks, ground and hydrothermal spring waters, etc. Of all the types of iron oxides, ferrihydrite has a largest distribution in living organisms, where it is found in the form of ferritin, an iron storage protein. Moreover, ferrihydrite is found to be present in some microbial communities, where it is produced by bacteria as a result of their metabolism. In addition to this, ferrihydrite has been found in several extraterrestrial materials, as meteorites and interplanetary dust particles.