Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-17T18:53:48.120Z Has data issue: false hasContentIssue false
  • English
  • Français

Kleberite, Fe3+Ti6O11(OH)5, a new ilmenite alteration product, from Königshain, northeast Germany

Published online by Cambridge University Press:  05 July 2018

I. E. Grey ,
K. Steinike  and
C. M. MacRae
I. E. Grey*
Affiliation:
CSIRO Process Science and Engineering, Box 312, Clayton South, Victoria 3169, Australia
K. Steinike
Affiliation:
Waldstrasse 8, OT Grunau, DE 12527 Berlin, Germany
C. M. MacRae
Affiliation:
CSIRO Process Science and Engineering, Box 312, Clayton South, Victoria 3169, Australia
*
* E-mail: ian.grey@csiro.au
Get access Rights & Permissions [Opens in a new window]

Abstract

Kleberite, ideally Fe3+Ti6O11(OH)5, is a new mineral (IMA 2012-023) from Tertiary sands at Königshain, Saxony, northeast Germany. It is also found in heavy mineral sands from the Murray Basin, southeast Australia and at Kalimantan, Indonesia. It occurs as rounded anhedral to euhedral translucent grains, 0.04 0.3 mm across, which are generally red-brown, but grade to orange with decreasing iron content. Associated minerals include ilmenite, pseudorutile, 'leucoxene', tourmaline and spinel. The density measured by pycnometry is 3.28 g cm-3, which is lower than the calculated density of 3.91 g cm-3, due to intragrain porosity which is not penetrated by the immersion fluid. The intragrain pores, of median diameter 18 nm, are partially filled with impurity phases including kaolinite, diaspore and quartz. Kleberite grains have a uniaxial (–) character, but localized regions are weakly biaxial (–) with 2V close to zero. The mean refractive index, calculated from reflectance measurements, is 2.16(3). The mean empirical formula from electron-microprobe analyses of 15 Königshain kleberite grains is Fe3+1.01Mg0.06Ti6O11.2(OH)4.8[Al0.59Si0.31P0.04O1.60·1.8H2O], where the formula element in square brackets represents impurities in the pores. Kleberite forms over a compositional range with [Ti]/[Fe + Ti] atomic ratios from 0.8–0.9. It has monoclinic symmetry, P21/c, with a = 7.537(1), b = 4.5795(4), c = 9.885(1) Å , β = 131.02(1)°. The six strongest lines in the powder X-ray diffraction (XRD) pattern [listed as d in Å (I)] are as follows: 1.676(100), 2.170(82), 2.466(27), 1.423(22), 3.933(8), 2.764(9). The structure was refined by the Rietveld method on powder XRD data to Rp = 6.3, Rwp = 8.1, RB = 4.0. Kleberite is isostructural with tivanite; their structural formulae are [Ti4+3□][Ti4+3Fe3+]O11 (OH)5 and [Ti4+4][V3+4]O12(OH)4, respectively. Kleberite has dominant Ti4+ in place of V3+ in the M(2) metal-atom site. The related mineral pseudorutile, [Ti4][(Fe3+,Ti)4](O,OH)16, with Fe3+ > Ti4+ has dominant Fe3+ in this site. Kleberite grains from different localities commonly contain residual MgO-rich ferrian ilmenite. The chemical and physical relationships between the ilmenite and coexisting kleberite are used to evaluate different alteration mechanisms involving selective leaching of divalent oxides from ilmenite and pseudomorphic replacement reactions, respectively.

Keywords

new mineralkleberitepseudorutileRietveld refinementilmenite alterationselective leaching of MgO-rich ferrian ilmenitetivanite-type structurepseudomorphic replacement reaction
Type
Letter
Information
Mineralogical Magazine , Volume 77 , Issue 1 , February 2013 , pp. 45 - 55
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2013

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Anand, R.R. and Gilkes, R.J. (1984) Weathering of ilmenite in a lateritic pallid zone. Clays and Clay Minerals, 32, 363–374.CrossRefGoogle Scholar
Anand, R.R. and Gilkes, R.J. (1985) Some alumina and silica in weathered ilmenite grains is present in clay minerals – a response to Frost et al. (1983). Mineralogical Magazine, 49, 141–145.CrossRefGoogle Scholar
Bautsch, H.J., Rohde, G., Sedlacek, P. and Zedler, A. (1978) Kleberit – Ein neues Eisen TitanOxidmineral aus Tertiaren Sänden. Zeitschrift für Geologische Wissenschaften, 6, 661–671.Google Scholar
Frost, M.T., Grey, I.E., Harrowfield, I.R. and Mason, K. (1983) The dependence of alumina and silica contents on the extent of alteration of weathered ilmenites from Western Australia. Mineralogical Magazine, 47, 201–208.CrossRefGoogle Scholar
Ghiorso, M.S. (1990) Thermodynamic properties of hematite–ilmenite–geikelite solid solutions. Contributions to Mineralogy and Petrology, 104, 645–667.CrossRefGoogle Scholar
Grey, I.E. and Li, C. (2001) Low temperature roasting of ilmenite – phase chemistry and applications. AusIMM Proceedings, 306, 35–42.Google Scholar
Grey, I.E. and Li, C. (2003) Hydroxylian pseudorutile derived from picroilmenite in the Murray Basin, southeastern Australia. Mineralogical Magazine, 67, 733–747.CrossRefGoogle Scholar
Grey, I.E. and Nickel, E.H. (1981) Tivanite, a new oxyhydroxide mineral from Western Australia, and its structural relationship to rutile and diaspore. American Mineralogist, 66, 866–871.Google Scholar
Grey, I.E. and Reid, A.F. (1975) The structure of pseudorutile and its role in the natural alteration of ilmenite. American Mineralogist, 60, 898–906.Google Scholar
Grey, I.E., Li, C. and Watts, J.A. (1983) Hydrothermal synthesis of goethite-rutile intergrowth structures and their relationship to pseudorutile. American Mineralogist, 68, 981–988.Google Scholar
Grey, I.E., Watts, J.A. and Bayliss, P. (1994) Mineralogical nomenclature: pseudorutile revalidated and neotype given. Mineralogical Magazine, 58, 597–600.CrossRefGoogle Scholar
Grey, I.E., Bordet, P., Wilson, N.C., Townend, R., Bastow, T.J. and Brunelli, M. (2010) A new Al-rich hydroxylian pseudorutile from Kalimantan, Indonesia. American Mineralogist, 95, 161–170.CrossRefGoogle Scholar
Harrison, R.J., Redfern, S.A.T. and Smith, R.I. (2000) In-situ study of the R3¯ to R3¯c phase transition in the ilmenite–hematite solid solution using time-of-flight neutron powder diffraction. American Mineralogist, 85, 194–205.CrossRefGoogle Scholar
Ignatiev, V.D. (1999) Solid-phase mechanism of the ilmenite leucoxenization. Lithology and Mineral Resources, 34, 184–189.Google Scholar
Jannsen, A., Putnis, A., Geisler, T. and Putnis, C.V. (2010) The experimental replacement of ilmenite by rutile in HCl solutions. Mineralogical Magazine, 74, 633–644.CrossRefGoogle Scholar
Putnis, A. (2002) Mineral replacement reactions: from macroscopic observations to microscopic mechanisms. Mineralogical Magazine, 66, 689–708.CrossRefGoogle Scholar
Putnis, A. and Putnis, C.V. (2007) The mechanism of reequilibration of solids in the presence of a fluid phase. Journal of Solid State Chemistry, 180, 1783–1786.CrossRefGoogle Scholar
Rodriguez-Carvajal, J. (1990) FULLPROF: A Program for Rietveld Refinement and Pattern Matching Analysis. Satellite meeting on powder diffraction of the XV Congress of the IUCr, Toulouse, France, 27 pp.Google Scholar
Steinike, K. (2008) Der Kleberit im nordöstlichen Teil Deutschlands (1949–1990. Staatsgebiet der DDR). Geohistorische Blätter, 11, 121–128.Google Scholar
Steinike, K. and Kaemmel, T. (2008) Kleberit – Pseudorutil/Hydroxy-Pseudorutil: zwei Welten – zwei Namen – ein Mineral? Geohistorische Blätter, 11, 1–8.Google Scholar