The Crystallization of Calcium Oxalate Hydrates Formed by Interaction Between Microorganisms and Minerals

Calcium Oxalates in Lichens on Surface of Apatite-Nepheline Ore (Kola Peninsula, Russia)

“…It is known that, on the calcite marble under the influence of the Aspergillus niger fungus, both whewellite and weddellite are formed under the experimental conditions [22,35,44]. According to our experiment, only calcium oxalate monohydrate, whewellite, was formed on the apatite rock under the action of the same fungus (Figure 7).…”

“…It was shown that, among the complex of factors determining the morphogenetic patterns of biogenic oxalate formation, one of the main roles belong to the metabolic activity of the lithobiont community organisms, which differs significantly from the activity of its individuals [44,45]. This result indicates a significant effect of microbial physiological processes on the chemistry of the crystallization medium in biofilms on the surface of various rocks and is well explained by selectively accumulation of elements from the environment by microorganisms during biofouling [31,46].…”

Synthesis and Characterization of (Ca,Sr)[C2O4]∙nH2O Solid Solutions: Variations of Phase Composition, Crystal Morphologies and in Ionic Substitutions

“…Besides, weddellite and whewellite often occur in crustose and foliose lichen thalli on the surface of Ca-bearing rocks and minerals [6][7][8][9]. Oxalate crystallization is a result of the interaction between metabolites of lichens and associated microscopic fungi with an underlying stone substrate in this case [10][11][12][13][14].…”

Oxalate formation under the hyperarid conditions of the Atacama desert as a mineral marker to provide clues to the source of organic carbon on Mars

“…While lichens are living forms that produce oxalates, there are other communities consisting of fungi and bacteria that have an essential role in the formation of these biominerals [ Hess et al ., ; Rusakov et al ., ]. Although the lichen communities are the main producer of oxalates in Atacama, the detection of oxalate minerals in the sedimentary infill of the Salar Grande demonstrates the potential of oxalates within chloride‐rich sedimentary rocks as biosignatures to detect microbial activity on Mars.…”

“…Although the lichen communities are the main producer of oxalates in Atacama, the detection of oxalate minerals in the sedimentary infill of the Salar Grande demonstrates the potential of oxalates within chloride‐rich sedimentary rocks as biosignatures to detect microbial activity on Mars. Particularly, some bacteria can form the same Ca‐bearing oxalate species that are formed by lichens [ Rusakov et al ., ]. As a consequence, they can become in persistent biosignatures due to its resistance to degradation and considerable facility of detection by current crystallographic and geochemical techniques.…”