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wyartite

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Journal Article
Published: 01 December 2006
The Canadian Mineralogist (2006) 44 (6): 1379–1385.
...Frank C. Hawthorne; Robert J. Finch; Rodney C. Ewing Abstract Dehydrated wyartite from the Shinkolobwe mine, Shaba, Democratic Republic of Congo, ideally Ca (CO 3 ) [U 5+ (U 6+ O 2 ) 2 O 4 (OH)] (H 2 O) 3 , is orthorhombic, a 11.2610(6), b 7.0870(4), c 16.8359(10) Å, V 1343.6(2) Å 3 , space group...
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Journal Article
Published: 01 September 1999
American Mineralogist (1999) 84 (9): 1456–1460.
...Peter C. Burns; Robert J. Finch Abstract Determination of the structure of wyartite provides the first evidence for a pentavalent-U mineral. The structure of wyartite, CaU (super 5+) (UO 2 ) 2 (CO 3 )O 4 (OH)(H 2 O) 7 , Z = 4, orthorhombic, a = 11.2706(8), b = 7.1055(5), c = 20.807(1) Aa, V...
Journal Article
Published: 01 February 1960
American Mineralogist (1960) 45 (1-2): 200–208.
...Joan R. Clark Abstract X -ray examinations of the mineral wyartite, assigned the chemical formula UO 2 ·6UO 3 ·2CO 2 ·3CaO·12-14H 2 O by Guillemin and Protas (1959), show that with passage of time the mineral is altering. Up to the present time two phases, both orthorhombic, have been found from...
Journal Article
Published: 01 December 2004
The Canadian Mineralogist (2004) 42 (6): 1683–1697.
...Michael Schindler; Frank C. Hawthorne; Christine Putnis; Andrew Putnis Abstract Interaction of concentrated acidic uranyl-bearing solutions at initial values of pH of 2.5 and 4.5 with calcite at 25°C in an open system results in formation of schoepite, becquerelite and wyartite-II. Interaction...
FIGURES | View All (4)
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Images taken with a reflection microscope: (a) <span class="search-highlight">wyartite</span> (violet) and becque...
Published: 01 December 2004
F ig . 3. Images taken with a reflection microscope: (a) wyartite (violet) and becquerelite (red) formed under acidic conditions. (b) Uranyl-bearing calcite (brown), becquerelite (red), schoepite (yellow) and liebigite (green) formed under basic conditions. (c) Fine-grained precipitate
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(a) The structural unit in <span class="search-highlight">wyartite</span>, with pentagonal bipyramids of U 6+  (y...
Published: 01 December 2004
F ig . 4. (a) The structural unit in wyartite, with pentagonal bipyramids of U 6+ (yellow) and U 5+ (red). The carbonate triangles, which share edges with the U 5+ pentagonal bipyramids, are omitted for clarity. (b) Calculated bond-valence deficiency per unit length [ vu /Å] of anion
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MISCELLANEOUS INFORMATION FOR DEHYDRATED <span class="search-highlight">WYARTITE</span>
Published: 01 December 2006
TABLE 1. MISCELLANEOUS INFORMATION FOR DEHYDRATED WYARTITE
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ATOM POSITIONS AND DISPLACEMENT FACTORS FOR DEHYDRATED <span class="search-highlight">WYARTITE</span>
Published: 01 December 2006
TABLE 2. ATOM POSITIONS AND DISPLACEMENT FACTORS FOR DEHYDRATED WYARTITE
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BOND-VALENCE ( vu ) TABLE* FOR DEHYDRATED <span class="search-highlight">WYARTITE</span>
Published: 01 December 2006
TABLE 4. BOND-VALENCE ( vu ) TABLE* FOR DEHYDRATED WYARTITE
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SELECTED INTERATOMIC DISTANCES (Å) AND ANGLES (°) IN DEHYDRATED <span class="search-highlight">WYARTITE</span>
Published: 01 December 2006
TABLE 3. SELECTED INTERATOMIC DISTANCES (Å) AND ANGLES (°) IN DEHYDRATED WYARTITE
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The arrangement of polyhedra in the structural unit of dehydrated <span class="search-highlight">wyartite</span> ...
Published: 01 December 2006
F ig . 2. The arrangement of polyhedra in the structural unit of dehydrated wyartite viewed down the c axis. The legend is as in Figure 1 ; red polyhedra: { U (2)O 6 } groups.
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Linkage of structural units by { Ca (1)ϕ 7 } polyhedra (green) in the struc...
Published: 01 December 2006
F ig . 3. Linkage of structural units by { Ca (1)ϕ 7 } polyhedra (green) in the structure of dehydrated wyartite viewed down the b axis. The legend is as in Figures 1 and 2 .
Journal Article
Published: 01 December 2016
European Journal of Mineralogy (2016) 28 (5): 959–967.
..., with both UO 6 and UO 7 bipyramids, which is similar to the sheets found in spriggite, ianthinite and wyartite. The sheets alternate with the interlayer, which contains K + , Ca 2+ and H 2 O molecules. Interstitial cations are linked into infinite chains that extend along [10-1]. Adjacent sheets are linked...
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Linkage of { U (2)O 6 } polyhedra (red) and (CO 3 ) triangles (black), and ...
Published: 01 December 2006
F ig . 1. Linkage of { U (2)O 6 } polyhedra (red) and (CO 3 ) triangles (black), and the coordination details of the Ca (1) site in dehydrated wyartite; yellow polyhedra: { U (1)O 7 } groups, OW sites [(H 2 O) groups] are shown as red circles, the Ca (1) site is shown as a green circle.
Journal Article
Published: 29 September 2023
The Canadian Journal of Mineralogy and Petrology (2023) 61 (5): 999–1020.
... minerals known to contain essential U 5+ , all possessing sheet-like structures. These include wyartite ( Burns & Finch 1999 ), dehydrated wyartitewyartite-II” ( Hawthorne et al. 2006 ), richetite ( Plášil 2017 ), and nollmotzite ( Plášil et al. 2018a ). In addition, the mixed-valence uranium...
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Journal Article
Published: 01 September 2017
American Mineralogist (2017) 102 (9): 1771–1775.
... of the U17Φ 7 polyhedral geometry in richetite with other compounds U−Φ (Å) O−U−O (°) BV (v.u.) Ref. Richetite (U17) 2.161 2.943 2.166 2.228 2.01 2.01 2.186 171.8 5.37 this work Wyartite (U3) 2.07 2.09 2.06 2.14 2.44 2.47 2.480 167.0 5.07 1 Dehyd. wyartite (U2...
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(a) Activity–activity diagram of log [Ca 2+ ]/[H] 2  versus  log [H 2 CO 3 ...
Published: 01 December 2004
). (c) Single crystals of liebigite in two different orientations: left, with the (001) face parallel to the surface of calcite; right, with (010) face parallel to the surface of calcite. (d) Elongate crystals of wyartite. (e) A pile of small crystals of becquerelite. (f) Schoepite crystals
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(a) Activity–activity diagram of log [Ca 2+ ]/[H] 2  versus  log [H 2 CO 3 ...
Published: 01 December 2004
of the crystals are defined by the [010], [100] and [110] edges. (e) AFM image of a single crystal of wyartite on calcite formed in a one-week batch experiment in uranyl acetate solution. (f) AFM image of single crystals of an unidentified phase formed during evaporation of uranyl acetate solution in contact
Journal Article
Published: 01 December 2004
The Canadian Mineralogist (2004) 42 (6): 1667–1681.
... at room temperature. After the batch experiments in weakly acidic solution, we identified the uranyl-bearing phases schoepite, becquerelite and wyartite II on the calcite surface, whereas phases such as U-bearing calcite, liebigite, wyartite II, becquerelite and schoepite have been observed after...
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Journal Article
Published: 01 March 2018
European Journal of Mineralogy (2018) 30 (2): 237–251.
...+ (UO 2 ) 4 O 6 (OH) 4 (H 2 O) 4 ](H 2 O) 5 P 2 1 cn 2503 188 5.56 1044.26 75.98 Wyartite CaU 5+ (UO 2 ) 2 (CO 3 )O 4 (OH)(H 2 O) 7 P 2 1 2 1 2 1 1666 156 5.29 824.52 62.06 Uranosphaerite Bi(UO 2 )O 2 (OH) P 2 1 / n 454 32 3.00 96.00 12.39 S.G.: space group...
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