Modern mineral deposits play an important role in evolutionary studies by providing clues to the formation of ancient lithified microbial communities. Here we report the presence of microbialite-forming microbial mats in different microenvironments at 32°C, 49°C, and 65°C around the geothermal spring from an abandoned oil drill in Ciocaia, Romania. The mineralogy and the macro- and microstructu...

The iron cycle in aquatic environments involves the reduction of ferric iron (Fe(III)) followed by the oxidation of ferrous iron (Fe(II)). Under natural conditions these reactions are microbially catalyzed. The reduction of Fe(III) is thought to be one of the most important microbially mediated processes in aquatic systems. Fe(II) tends to be soluble and mobile in water, while Fe(III) tends to ...

Raman spectroscopy complimented with infrared spectroscopy has been used to study a series of selected natural halogenated carbonates from different origins including bastnasite, parisite and northupite. The position of CO3 symmetric stretching vibration varies with mineral composition. An additional band for northupite at 1107 cm is observed. Raman spectra of bastnasite, parisite and northupit...

This study investigated the effects of a combination of calcium and magnesium carbonate intestinal phosphate binders, associated with natural reno-protectant substances (the uraemic toxin binder chitosan, vasoactive peptides and an extract of Astragalus membranaceus) (Pronefra®, Virbac, France) on blood parameters and mineral balance in cats. Ten cats, 2 to 5 years old at day 0, were given the ...

Despite the proclamation of Lowenstam and Weiner that crustaceans are the "champions of mineral mobilization and deposition of the animal kingdom," relatively few proteins from the two main calcification sites in these animals, i.e., the exoskeleton and the transient calcium storage organs, have been identified, sequenced, and their roles elucidated. Here, a 65-kDa protein (GAP 65) from the gas...

Indium (In) is commonly hosted in Sn-rich deposits but rarely reported in Sn-poor deposits. However, an In-rich and Sn-poor skarn deposit, the Qibaoshan Cu-Zn-Pb deposit, has been identified in south China. Geochemical analyses were undertaken on 23 samples representing the following mineral assemblages: sphalerite-pyrite, pyrite-chalcopyrite, pyrite-sphalerite-galena-chalcopyrite, pyrite, magn...

Gases contained within near-surface marine sediments can be derived from multiple sources: shallow microbial activity, thermal cracking of organic matter and inorganic materials, or magmatic-mantle degassing. Each origin will display a distinctive hydrocarbon and non-hydrocarbon composition as well as compound-specific isotope signature and thus the interpretation of origin should be relatively...

Laboratory experiments and field trials have shown that oil recovery from carbonate reservoirs can be increased by modifying the brine composition injected during recovery in a process termed controlled salinity water-flooding (CSW). However, CSW remains poorly understood and there is no method to predict the optimum CSW composition. This work demonstrates for the first time that improved oil r...

This study presents, for the first time, field evidence of complete, irreversible processing of solid calcium carbonate (calcite)-containing particles and quantitative formation of liquid calcium nitrate particles apparently as a result of heterogeneous reaction of calcium carbonate-containing mineral dust particles with gaseous nitric acid. Formation of nitrates from individual calcite and sea...

Hyperphosphatemia is considered as an independent risk factor for surrogate clinical endpoints like vascular calcification (VC) and bone disease, or hard clinical outcomes like cardiovascular events. To date, various treatment options for phosphate removal or reduction are available. The great expectations put into calcium-based phosphate binders were mitigated because of their possible contrib...