Detailed Information on Publication Record
2017
Gauthierite, KPb[(UO2)(7)O-5(OH)(7)]center dot 8H(2)O, a new uranyl-oxide hydroxy-hydrate mineral from Shinkolobwe with a novel uranyl-anion sheet-topology
OLDS, Travis, Jakub PLÁŠIL, Antony KAMPF, Radek ŠKODA, Peter BURNS et. al.Basic information
Original name
Gauthierite, KPb[(UO2)(7)O-5(OH)(7)]center dot 8H(2)O, a new uranyl-oxide hydroxy-hydrate mineral from Shinkolobwe with a novel uranyl-anion sheet-topology
Authors
OLDS, Travis (840 United States of America), Jakub PLÁŠIL (203 Czech Republic), Antony KAMPF (840 United States of America), Radek ŠKODA (203 Czech Republic, guarantor, belonging to the institution), Peter BURNS (840 United States of America), Jiří ČEJKA (203 Czech Republic), Vincent BOURGOIN (250 France) and Jean-Claude BOULLIARD (250 France)
Edition
European Journal of Mineralogy, STUTTGART, E SCHWEIZERBARTSCHE VERLAGSBUCHHANDLUNG, 2017, 0935-1221
Other information
Language
English
Type of outcome
Článek v odborném periodiku
Field of Study
10504 Mineralogy
Country of publisher
Germany
Confidentiality degree
není předmětem státního či obchodního tajemství
Impact factor
Impact factor: 1.190
RIV identification code
RIV/00216224:14310/17:00100328
Organization unit
Faculty of Science
UT WoS
000396823700011
Keywords in English
gauthierite; new mineral; uranyl-oxide hydroxy-hydrate; crystal structure; topology; oxidation zone; Shinkolobwe
Tags
International impact, Reviewed
Změněno: 4/4/2018 11:14, Ing. Nicole Zrilić
Abstract
V originále
Gauthierite, KPb[(UO2)(7)O-5(OH)(7)]center dot 8H(2)O, is a new uranyl-oxide hydroxy-hydrate mineral from the Shinkolobwe Mine, Democratic Republic of Congo, Africa. It occurs on a matrix of uraninite-bearing quartz gangue associated with soddyite and a minor metazeunerite-metatorbernite series mineral. It is a product of oxidation-hydration weathering of uraninite. Gauthierite is monoclinic, P2(1)/c, with a = 29.844(2) angstrom, b = 14.5368(8) angstrom, c = 14.0406(7) angstrom, beta = 103.708(6)degrees, V = 5917.8(6) angstrom(3) and Z = 8. Prismatic crystals have pronounced lengthwise striations and reach about 1 mm in length. Gauthierite is yellowish orange with a light orange streak and vitreous lustre. The Mohs hardness is similar to 3 to 4. It is brittle with an uneven fracture and perfect cleavage on {0 1 0}. The calculated density based on the empirical formula is 5.437 g/cm(3). Optically, gauthierite is biaxial (-), with alpha = 1.780(5), beta = 1.815(5), gamma = 1.825(5) (white light), 2V(meas.) = 58(1)degrees; dispersion is extreme (r >>nu). The optical orientation is X = b, Y approximate to a*, Z approximate to c (or X = b, Y<^>a=14 degrees in obtuse beta); it is pleochroic with X very pale yellow, Y and Z orange-yellow; X << Y approximate to Z. Electron microprobe analyses (average of 9) provided: K2O 1.29, PbO 7.17, UO3 82.10, H2O 8.78 (structure), total 99.34 wt.%. The empirical formula (based on 34 O a.p.f.u.) is: K0.67Pb0.78U7O34H23.77. The ideal formula is KPb[(UO2)(7)O-5(OH)(7)](H2O)(8), which requires K2O 1.90, PbO 9.00, UO3 80.74, H2O 8.35, total 100 wt.%. Raman and infrared spectral data confirm the presence of UO22+, OH- and molecular H2O. The eight strongest powder X-ray diffraction lines are [d(obs) in angstrom (hkl) I-rel]: 7.28 (020,400) 49, 3.566 (040, -802, -204) 67, 3.192 (622, -224) 100, 2.541 (-842, -244) 18, 2.043 (406) 14, 2.001 (662, -264, 14.2.0) 23, 1.962 (426, -146) 14, and 1.783 (12.0.4, -10.4.6) 17. The crystal structure of gauthierite (R = 0.0567 for 6997 reflections with [I>3 sigma(I)]) contains uranyl-(hydroxo)-oxide sheets with a novel topology that is similar to that of vandendriesscheite, but with a unique chain sequence UDPDPDUPUP, P-4(UD)(6). Adjacent sheets are linked through K+ and Pb2+ cations (the lone 6s(2) pair on Pb atoms is stereoactive).
Links
| MUNI/A/1316/2015, interní kód MU |
|