『Abstract
　Study of carbonate inclusions in the Mamatwan-type oxide ores (braunite lutites) made it possible to reveal residual microbial structures in them. Their presence in manganese ores, the type of manganese oxide mineralization, isotope signatures of manganese carbonates, and available literature data on the geology of the Kalahari manganese field suggest that manganese ore formation was widespread at the postsedimentary stage of transformation of the primary microbial sediment. The deposit can be referred to the hydrothermal-metasomatics type.』

Overview of the geological setting and ores in deposits of the Kalahari ore field
　General geological characteristics
　　Ore types
　　Specific features of the microscopic structure of ores
Geochemistry of isotopes
Genesis of ores
Conclusions
Acknowledgments
References