Article
Licensed
Unlicensed Requires Authentication

Lakebogaite, CaNaFe23+H(UO2)2(PO4)4(OH)2(H2O)8, a new uranyl phosphate with a unique crystal structure from Victoria, Australia

  • EMAIL logo , , , and
Published/Copyright: April 1, 2015
Become an author with De Gruyter Brill
Author Information
American Mineralogist
From the journal American Mineralogist Volume 93 Issue 4

Abstract

Lakebogaite, ideally CaNaFe23+H(UO2)2(PO4)4(OH)2(H2O)8, is a new Ca-Na-Fe uranyl phosphate mineral from a quarry in Upper Devonian granite near Lake Boga, northern Victoria, Australia. It is associated with Na-analogue of meurigite (IMA 2007-024), torbernite, and saléeite on a matrix of microcline, albite, smoky quartz, and muscovite. Lakebogaite occurs as bright lemon-yellow transparent prismatic crystals up to 0.4 mm across. The crystals have a vitreous luster and a pale yellow streak. Mohs hardness is about 3. The fracture is even to conchoidal. In transmitted light, the mineral is pale yellow with very weak pleochroism: X = yellow, Y = grayish yellow, Z = grayish yellow: dispersion r > v, strong. Lakebogaite crystals are biaxial (+), with slightly variable refractive indices within the ranges: nα = 1.650(2)-1.652(2), nβ = 1.660(4)-1.664(3), nγ = 1.681(3)-1.686(2), measured using white light, and with 2Vmeas = 80-85° and 2Vcalc = 70-74°. Orientation: Y = b; crystals are elongated along [010], resulting in straight extinction. The empirical chemical formula (mean of nine electron microprobe analyses) calculated on the basis of 30 anions is (Ca1.00Na0.80Sr0.10)Σ1.90(Fe3+1.85Al0.30)Σ2.15(UO2)1.80 (PO4)4.07(OH,H2O)10.12. Lakebogaite is monoclinic, space group Cc, a = 19.6441(5), b = 7.0958(2), c = 18.7029(5) Å, β = 115.692(1)°, V = 2349.3(7) Å3, Z = 4. The seven strongest reflections in the powder X-ray diffraction pattern are [dobs in Å (I) (hkl)]: 6.60 (100) (110), 3.16 (40) (514̅, 604̅), 4.07 (20) (404̅), 3.80 (20) (314̅), 3.56 (20) (020, 312), 3.31 (20) (114, 220), 2.797 (20) (006). The crystal structure was solved from single-crystal X-ray diffraction data and refined to R1 = 0.038 on the basis of 5222 unique reflections with F > 4σF. It comprises pairs of edge-shared UO7 pentagonal bipyramids that are inter-linked via corner-sharing with PO4 tetrahedra, to form chains parallel to the c-axis. Each UO7 polyhedron also shares one of its edges with another PO4 tetrahedron. The (UO2)2(PO4)4 chains are cross-linked via corner-sharing between the PO4 tetrahedra and Fe3+O4(OH)2 octahedra. The octahedra join together by corner-sharing via OH anions to form chains parallel to b. The Na+ and Ca2+ cations, and 4 water molecules occupy eight-sided channels along [010]. The remaining water molecules occupy large ten-sided channels directed along [001] and intersecting the [010] channels. The mineral is named for the nearest township.

Keywords: Lakebogaite; new mineral; uranyl phosphate; Lake Boga quarry; north-western Victoria; Australia; crystal structure; (UO2)2(PO4)4 chains
Received: 2007-6-4
Accepted: 2007-11-26
Published Online: 2015-4-1
Published in Print: 2008-4-1

© 2015 by Walter de Gruyter Berlin/Boston

Articles in the same Issue

  1. Compositional variability and crystal structural features of guanacoite
  2. Interferometric study of pyrite surface reactivity in acidic conditions
  3. White mica domain formation: A model for paragonite, margarite, and muscovite formation during prograde metamorphism
  4. High-pressure phase transitions in MgSiO3 orthoenstatite studied by atomistic computer simulation
  5. Time-resolved synchrotron powder X-ray diffraction study of magnetite formation by the Fe(III)-reducing bacterium Geobacter sulfurreducens
  6. Low-temperature calorimetric and magnetic data for natural end-members of the axinite group
  7. Temperature derivatives of elastic wave velocities in plagioclase (An51±1) above and below the order-disorder transition temperature
  8. Disordered silica with tridymite-like structure in the Twiggs clay
  9. Crystal structures of synthetic melanotekite (Pb2Fe2Si2O9), kentrolite (Pb2Mn2Si2O9), and the aluminum analogue (Pb2Al2Si2O9)
  10. Structure and reactivity of synthetic Co-substituted goethites
  11. The crystal chemistry of Fe-bearing sphalerites: An infrared spectroscopic study
  12. Effects of hydration on the structure and compressibility of wadsleyite, β-(Mg2SiO4)
  13. Metastability of sillimanite relative to corundum and quartz in the kyanite stability field: Competition between stable and metastable reactions
  14. Diffusion, discontinuous precipitation, metamorphism, and metasomatism: The complex history of South African upper-mantle symplectites
  15. Thermal behavior of a Ti-rich phlogopite from Mt. Vulture (Potenza, Italy): An in situ X-ray single-crystal diffraction study
  16. The high-pressure behavior of an Al- and Fe-rich natural orthopyroxene
  17. High-pressure phase relation of MnSiO3 up to 85 GPa: Existence of MnSiO3 perovskite
  18. Linking Mössbauer and structural parameters in elbaite-schorl-dravite tourmalines
  19. Synchrotron powder X-ray diffraction study of the structure and dehydration behavior of palygorskite
  20. Maskelynite-hosted apatite in the Chassigny meteorite: Insights into late-stage magmatic volatile evolution in martian magmas
  21. Eskolaite associated with diamond from the Udachnaya kimberlite pipe, Yakutia, Russia
  22. Lakebogaite, CaNaFe23+H(UO2)2(PO4)4(OH)2(H2O)8, a new uranyl phosphate with a unique crystal structure from Victoria, Australia
  23. Letter. Crystal structure and Raman spectrum of hydroxyl-bästnasite-(Ce), CeCO3(OH)
https://doi.org/10.2138/am.2008.2706
Keywords for this article
Lakebogaite; new mineral; uranyl phosphate; Lake Boga quarry; north-western Victoria; Australia; crystal structure; (UO2)2(PO4)4 chains

Articles in the same Issue

  1. Compositional variability and crystal structural features of guanacoite
  2. Interferometric study of pyrite surface reactivity in acidic conditions
  3. White mica domain formation: A model for paragonite, margarite, and muscovite formation during prograde metamorphism
  4. High-pressure phase transitions in MgSiO3 orthoenstatite studied by atomistic computer simulation
  5. Time-resolved synchrotron powder X-ray diffraction study of magnetite formation by the Fe(III)-reducing bacterium Geobacter sulfurreducens
  6. Low-temperature calorimetric and magnetic data for natural end-members of the axinite group
  7. Temperature derivatives of elastic wave velocities in plagioclase (An51±1) above and below the order-disorder transition temperature
  8. Disordered silica with tridymite-like structure in the Twiggs clay
  9. Crystal structures of synthetic melanotekite (Pb2Fe2Si2O9), kentrolite (Pb2Mn2Si2O9), and the aluminum analogue (Pb2Al2Si2O9)
  10. Structure and reactivity of synthetic Co-substituted goethites
  11. The crystal chemistry of Fe-bearing sphalerites: An infrared spectroscopic study
  12. Effects of hydration on the structure and compressibility of wadsleyite, β-(Mg2SiO4)
  13. Metastability of sillimanite relative to corundum and quartz in the kyanite stability field: Competition between stable and metastable reactions
  14. Diffusion, discontinuous precipitation, metamorphism, and metasomatism: The complex history of South African upper-mantle symplectites
  15. Thermal behavior of a Ti-rich phlogopite from Mt. Vulture (Potenza, Italy): An in situ X-ray single-crystal diffraction study
  16. The high-pressure behavior of an Al- and Fe-rich natural orthopyroxene
  17. High-pressure phase relation of MnSiO3 up to 85 GPa: Existence of MnSiO3 perovskite
  18. Linking Mössbauer and structural parameters in elbaite-schorl-dravite tourmalines
  19. Synchrotron powder X-ray diffraction study of the structure and dehydration behavior of palygorskite
  20. Maskelynite-hosted apatite in the Chassigny meteorite: Insights into late-stage magmatic volatile evolution in martian magmas
  21. Eskolaite associated with diamond from the Udachnaya kimberlite pipe, Yakutia, Russia
  22. Lakebogaite, CaNaFe23+H(UO2)2(PO4)4(OH)2(H2O)8, a new uranyl phosphate with a unique crystal structure from Victoria, Australia
  23. Letter. Crystal structure and Raman spectrum of hydroxyl-bästnasite-(Ce), CeCO3(OH)
Downloaded on 14.4.2026 from https://www.degruyterbrill.com/document/doi/10.2138/am.2008.2706/html
Scroll to top button