On the lepidocrocite formation in soils.

The data obtained on lepidocrocite (y-FeOOH) in two soil complexes of different climatic regions (the Stavropol region and the Kolyma Lowland) add to the existing knowledge about its genesis in soils. The synthesis of this mineral is possible in conditions of sharp changes in the redox potential favoring the release of free Fe 2+ from the lattice of iron-containing silicates and a close to neutral soil reaction. The stage of slow oxidation of Fe 2+ is crucial for the synthesis of lepidocrocite. This process is favored by a high content of soil organic matter. The mineralogical composition of soil, as well as soil texture, exerts a significant effect on the synthesis of lepidocrocite and the degree of its crystallization.