The new K, Pb-bearing uranyl-oxide mineral kroupaite: Crystal-chemical implications for the structures of uranyl-oxide hydroxy-hydrates

Investor logo

Warning

This publication doesn't include Faculty of Arts. It includes Faculty of Science. Official publication website can be found on muni.cz.
Authors

PLÁŠIL Jakub KAMPF Anthony R. OLDS Travis A. SEJKORA Jiří ŠKODA Radek BURNS Peter C. CEJKA Jiří

Year of publication 2020
Type Article in Periodical
Magazine / Source American Mineralogist
MU Faculty or unit

Faculty of Science

Citation
Web https://doi.org/10.2138/am-2020-7311
Doi http://dx.doi.org/10.2138/am-2020-7311
Keywords Kroupaite; new mineral species; uranyl-oxide hydroxy-hydrate; crystal structure; Voronoi-Dirichlet polyhedral; Cs-135; Sr-90; Jachymov
Description Kroupaite (IMA 2017-031), ideally KPb0.5[(UO2)(8)O-4(OH)(10)]center dot 10H(2)O, is a new uranyl-oxide hydroxylhydrate mineral found underground in the Svornost mine, Jachymov, Czechia. Electron-probe micro-analysis (WDS) provided the empirical formula (K(1.2)8Na(0.07))Sigma(1.35)(Pb0.23Cu0.14Ca0.05Bi0.03Co0.02Al0.01)(Sigma 0.48) [(UO2)(7.90)(SO4)(0.04)O-4.04(OH)(10.00)]center dot 10H(2)O, on the basis of 40 O atoms apfu. Sheets in the crystal structure of kroupaite adopt the fourmarierite anion topology, and therefore kroupaite belongs to the schoepite-family of minerals with related structures differing in the interlayer composition and arrangement, and charge of the sheets. Uptake of dangerous radionuclides (Sr-90 or Cs-135) into the structure of kroupaite and other uranyl-oxide hydroxy-hydrate is evaluated based on crystal-chemical considerations and Voronoi-Dirichlet polyhedra measures. These calculations show the importance of these phases for the safe disposal of nuclear waste.
Related projects:

You are running an old browser version. We recommend updating your browser to its latest version.