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Decrespignyite-(Y), a new copper yttrium rare earth carbonate chloride hydrate from Paratoo, South Australia

Published online by Cambridge University Press:  05 July 2018

K. Wallwork ,
U. Kolitsch ,
A. Pring  and
L. Nasdala
K. Wallwork*
Affiliation:
School of Chemistry, Physics and Earth Sciences, The Flinders University of South Australia, GPO Box 2100 Adelaide, South Australia 500, Australia
U. Kolitsch
Affiliation:
Institut für Mineralogie und Kristallographie, Universität Wien, Geozentrum, Althanstr. 14, A-1090 Vienna, Austria
A. Pring
Affiliation:
School of Chemistry, Physics and Earth Sciences, The Flinders University of South Australia, GPO Box 2100 Adelaide, South Australia 500, Australia Mineralogy Department, South Australian Museum, North Terrace, Adelaide, S.A. 5000, Australia Department of Geology and Geophysics, University of Adelaide, North Terrace, Adelaide, S.A. 5000, Australia
L. Nasdala
Affiliation:
Institut für Geowissenschaften – Mineralogie, Johannes Gutenberg-Universität, D-55099 Mainz, Germany
*
*E-mail: pring.allan@saugov.sa.gov.au
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Abstract

Decrespignyite-(Y) is a new copper yttrium rare earth carbonate chloride hydrate from the Paratoo copper mine, near Yunta, Olary district, South Australia. Decrespignyite-(Y) occurs as blue crusts, coatings and fillings in thin fissures on the slatey country rock. Individual pseudohexagonal platelets are typically 10–50 µm in maximum dimension and are often curved. Associated minerals include caysichite-(Y), donnayite-(Y), malachite and kamphaugite-(Y). Electron microprobe and CHN analyses gave: Y2O3 42.2; La2O3 0.1; Pr2O3 0.1; Nd2O3 1.3; Sm2O3 1.0; Gd2O3 4; Tb2O3 0.4; Dy2O3 3.7; Ho2O3 2.6; Er2O3 2.5; CaO 0.5; CuO 10.9; Cl 3.0; CO2 19.8; H2O 10.8, yielding an empirical formula of (Y3.08Gd0.22Dy0.16Ho0.11Er0.10Nd0.06Sm0.05Tb0.02La0.02Pr0.01Ca0.08)∑3.91Cu1.12(CO3)3.70-Cl0.7(OH)5.79·2.4H2O. The simplified formula is (Y,REE)4Cu(CO3)4Cl(OH)5·2H2O. The mineral is royal blue to turquoise-blue in colour, transparent, with a pearly to vitreous lustre and a pale blue streak. No cleavage was observed but the morphology suggests that cleavage would be on [010]. The Mohs' hardness is estimated to be 4. The strongest lines in the X-ray powder pattern are {dobs (Iobs) (hkl)} 22.79 (30) (010); 7.463 (30) (001); 7.086 (50) (011); 6.241 (100) (021); 4.216 (30) (12); 3.530 (40) (022); 3.336 (30) (032); 2.143 (30) (222, 01). The powder diffraction pattern was indexed on a monoclinic cell with a = 8.899(6), b = 22.77(2), c = 8.589(6)Å, β = 120.06(5)°, V = 1506.3(7) Å3 and Z = 4. The structure of the new mineral could not be determined but powder diffraction data indicate the space group is P2, Pm or P2/m. The measured density is 3.64(2) g/cm3 and the calculated density is 3.645 g/cm3. Decrespignyite-(Y) is biaxial negative with α = 1.604(4) and γ = 1.638(3) with β very close to γ pleochroism is medium strong; X very pale bluish, Y and Z bluish (with greenish tint). Decrespignyite-(Y) is a supergene mineral which precipitated from mildly basic carbonated ground waters. The mineral is named after Robert Champion de Crespigny, a prominent figure in the Australian mining industry and chancellor of the University of Adelaide.

Keywords

decrespignyite-(Y)new mineralrare earth carbonatesParatoo depositSouth Australia
Type
Research Article
Information
Mineralogical Magazine , Volume 66 , Issue 1 , February 2002 , pp. 181 - 188
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2002

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References

Boyle, D.R. (1997) Iodargyrite as an indicator of arid climatic conditions and its association with gold-bearing glacial tills of the Chibougamau-Chapais area, Quebec. Canadian Mineralogist, 35, 23–34.Google Scholar
Brown, H.Y.L. (1908) The Mines of South Australia. Reprint of 4th edition, Bristow, C.E., Adelaide, Australia, 382 pp.Google Scholar
Drexel, J.F., Preiss, W.V. and Parker, AJ. (1993) The geology of South Australia, Geological Survey of South Australia Bulletin 54, vol. 1, 177–185.Google Scholar
Garrels, R.M. and Christ, C.L. (1965) Solutions, Minerals, and Equilibria. Harper & Row, New York, USA.Google Scholar
Hawthorne, F.C. (1985) Refinement of the crystal structure of botallackite. Mineralogical Magazine, 49, 87–89.CrossRefGoogle Scholar
Hogarth, D.D., Chao, G.Y., Plant, A.G. and Steacy, H.R. (1974) Caysichite, a new silico-carbonate of yttrium and calcium. Canadian Mineralogist, 12, 293–298.Google Scholar
Hunter, B.A. (1998) Rietica – A Visual Rietveld Program. Commission on Powder Diffraction Newsletter, 20, 21.Google Scholar
Kolitsch, U. (2002) Caysichite-(Y), donnayite-(Y), kamphaugite-(Y) and other rare-earth carbonates from the Paratoo copper mine, South Australia (in prep.).Google Scholar
Le Bail, A, Duroy, H., and Fourquet, J.L. (1988) Ab- initio structure determination of LiSbWO6 by X-ray powder diffraction. Materials Research Bulletin, 23, 447–452.CrossRefGoogle Scholar
Libowitzky, E. (1999) Correlation of O-H stretching frequencies and O-H·s··O hydrogen bond lengths in minerals. Monatshefte für Chemie, 130, 1047–1059.CrossRefGoogle Scholar
Nasdala, L. and Massonne, H.-J. (2000) Microdiamonds from the Saxonian Erzgebirge, Germany: in situ micro-Raman characterisation. European Journal of Mineralogy, 12, 495–498.CrossRefGoogle Scholar
Ni, Y., Hughes, J.M. and Mariano, A.N. (1993) The atomic arrangement of bastnäsite-(Ce), Ce(CO3)F, and structural elements of synchysite-(Ce), röntgen- ite-(Ce), and parisite-(Ce). American Mineralogist, 78, 415–418.Google Scholar
Ni, Y, Post, J.E. and Hughes, J.M. (2000) The crystal structure of parisite-(Ce). American Mineralogist, 85, 251–258.CrossRefGoogle Scholar
Nixon, L.G.B. (1967) Paratoo copper deposit. Mining Review (Adelaide), Volume Date 1965, No. 123, 8–20.Google Scholar
Raade, G. and Brastad, K. (1993) Kamphaugite-(Y), a new hydrous Ca-(Y, REE)- carbonate mineral. European Journal of Mineralogy, 5, 679–83.CrossRefGoogle Scholar
Rłmming, C, Kocharian, A.K. and Raade, G. (1993) The crystal structure of kamphaugite-(Y). European Journal of Mineralogy, 5, 685–690.CrossRefGoogle Scholar
Rousseau, D. L., Baumann, R. P. and Porto, S. P. S. (1981) Normal mode determination in crystals. Journal of Raman Spectroscopy, 10, 253–290.CrossRefGoogle Scholar
Voronova, A.A. and Vainshtein, B.K. (1973) Electron diffraction determination of the crystal structure of Cu(OH)Cl. Kristallografiya, 18, 106–111.Google Scholar
Williams, P.A. (1990) Oxide Zone Geochemistry. Ellis Horwood, New York, USA, 286 pp.Google Scholar
Woodcock, J.T. (1966) Treatment of Oxidized Copper Ore from Paratoo, South Australia. CSIRO Mining Department, University of Melbourne, Ore Dressing Investation Report No. 666, 9 pp.Google Scholar