Source of Raw Materials and Its Processing for the Manufacturing of Ptolemaic Faience Bowls from Tell Atrib (Nile Delta, Egypt).

The provenance of siliceous grain material, the basic source of manufacturing faience items, is still a matter of discussion. The study methods applied so far have not brought satisfactory outcomes, and the results are ambiguous and problematic. Archaeological evidence has also not supplied adequate proof for establishing the sites where the source material was obtained and the methods of its preparation.

Potentiometric and electrokinetic signatures of iron(II) interactions with (α,γ)-Fe2O3.

The electrochemical signatures of Fe(II) interactions with iron(III) oxides are poorly understood, despite their importance in controlling the amount of mobilized iron. Here, we report the potentiometric titration of α,γ-Fe2O3 oxides exposed to Fe(II) ions. We monitored in situ surface and ζ potentials, the ratio of mobilized ferric to ferrous, and the periodically analyzed nanoparticle crystal structure using X-ray diffraction.

Bioweathering of Kupferschiefer black shale (Fore-Sudetic Monocline, SW Poland) by indigenous bacteria: implication for dissolution and precipitation of minerals in deep underground mine.

The Upper Permian polymetallic, organic-rich Kupferschiefer black shale in the Fore-Sudetic Monocline is acknowledged to be one of the largest Cu-Ag deposits in the world. Here we report the results of the first study of bioweathering of this sedimentary rock by indigenous heterotrophic bacteria. Experiments were performed under laboratory conditions, employing both petrological and microbiological methods, which permitted the monitoring and visualization of geomicrobiological processes.