Uranium as a possible criterion for the hydro-chemical alteration of betafite

• Published in: Physics and chemistry of minerals Vol. 45; no. 6; pp. 549 - 562
• Main Authors: Hosseinpour Khanmiri, Mohammad, Yanson, Svetlana Yu, Fomin, Edward V., Titov, Anatoly V., Grebeniuk, Andrey V., Polekhovsky, Yury S., Bogdanov, Roman V.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.06.2018; Springer Nature B.V
• Subjects: Cations; Chemical composition; Chemical reactions; Crystallography and Scattering Methods; Earth and Environmental Science; Earth Sciences; Geochemistry; Geological history; Leaching; Mineral Resources; Mineralogy; Organic chemistry; Original Paper; Uranium; Leaching kinetic; Calculations of mineral formula; Chemical shift of X-ray Lα; line; Metamict minerals; Redox-state of uranium; Half-leaching time; Chemical weathering
• ISSN: 0342-1791; 1432-2021
• DOI: 10.1007/s00269-018-0941-6

Hydro-chemical processes significantly alter the original composition of metamict minerals. In the work presented here, an attempt was made to reconstruct the chemical composition of betafite in the earlier stages of its geological history. The time scale is determined by the leaching rate of the isotope 238 U, a process that takes its course in line with first-order kinetics, or something close to it. The leaching rate constant of this uranium isotope was assessed. Based on available data in the literature, the hydro-chemical behavior of various atoms in group A of betafite was analyzed. The chemical composition of the mineral was calculated taking into account the total charge of the cations that the betafite had at the time it was formed, or possibly the last time it was completely reformed as a result of diverse endogenic processes.