Hostname: page-component-586b7cd67f-rcrh6 Total loading time: 0 Render date: 2024-11-22T06:06:55.608Z Has data issue: false hasContentIssue false

Lead-tellurium oxysalts from Otto Mountain near Baker, California, USA: XII. Andychristyite, PbCu2+Te6+O5(H2O), a new mineral with hcp stair-step layers

Published online by Cambridge University Press:  02 January 2018

Anthony R. Kampf*
Affiliation:
Mineral Sciences Department, Natural History Museum of Los Angeles County, 900 Exposition Blvd., Los Angeles, CA 90007, USA
Mark A. Cooper
Affiliation:
Department of Geological Sciences, University of Manitoba, Winnipeg, Manitoba, R3T 2N2, Canada
Stuart J. Mills
Affiliation:
Geosciences, Museum Victoria, GPO Box 666, Melbourne 3001, Victoria, Australia
Robert M. Housley
Affiliation:
Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA
George R. Rossman
Affiliation:
Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA
*

Abstract

Andychristyite, PbCu2+Te6+O5(H2O), is a new tellurate mineral from Otto Mountain near Baker, California, USA. It occurs in vugs in quartz in association with timroseite. It is interpreted as having formed from the partial oxidation of primary sulfides and tellurides during or following brecciation of quartz veins. Andychristyite is triclinic, space group P1̄, with unit-cell dimensions a = 5.322(3), b= 7.098(4), c = 7.511 (4) Å, α = 83.486(7), β = 76.279(5), γ = 70.742(5)°, V = 260.0(2) Å3 and Z = 2. It forms as small tabular crystals up to ∼50 μm across, in sub-parallel aggregates. The colour is bluish green and the streak is very pale bluish green. Crystals are transparent with adamantine lustre. The Mohs hardness is estimated at between 2 and 3. Andychristyite is brittle with an irregular fracture and one perfect cleavage on {001}. The calculated density based on the empirical formula is 6.304 g/cm3. The mineral is optically biaxial, with large 2V, strong dispersion, and moderate very pale blue-green to medium blue-green pleochroism. The electron microprobe analyses (average of five) provided: PbO 43.21, CuO 15.38, TeO3 35.29, H2O 3.49 (structure), total 97.37 wt.%. The empirical formula (based on 6 O apfu) is: Pb0.98Cu2+0.98Te6+1.02O6H 1.96. The Raman spectrum exhibits prominent features consistent with the mineral being a tellurate, as well as an OH stretching feature confirming a hydrous component. The eight strongest powder X-ray diffraction lines are [dobs in Å(I)(hkl)]: 6.71(16)(010), 4.76(17)(110), 3.274(100)(120,102,012), 2.641(27)(102, 211, 112), 2.434(23)(multiple), 1.6736(17)(multiple), 1.5882(21)(multiple) and 1.5133(15)(multiple). The crystal structure of andychristyite (R1 = 0.0165 for 1511 reflections with Fo > 4σF) consists of stair-step-like hcp polyhedral layers of Te6+O6 and Cu2+O6 octahedra parallel to {001}, which are linked in the [001] direction by bonds to interlayer Pb atoms. The structures of eckhardite, bairdite, timroseite and paratimroseite also contain stair-step-like hcp polyhedral layers.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2016

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

Atencio, D., Andrade, M.B., Christy, A.G., Gieré, R. and Kartashov, P.M. (2010) The pyrochlore-supergroup minerals nomenclature. The Canadian Mineralogist, 48, 673698.CrossRefGoogle Scholar
Blasse, G. and Hordijk, W. (1972) The vibrational spectrum of Ni3TeO6 and Mg3TeO6 . Journal of Solid State Chemistry, 5, 395397.CrossRefGoogle Scholar
Brown, I.D. and Altermatt, D. (1985) Bond-valence parameters from a systematic analysis of the inorganic crystal structure database. Acta Crystallographica, B41, 244247.CrossRefGoogle Scholar
Burns, E.C, Fluth, II, Smith, J.V., Eng, P., Steele, I.M. and Housley, R.M. (2000) Quetzalcoatlite: new octahedral-tetrahedral structure from 2 x 2 x 40 micron crystal at the Advanced Photon Source-GSE-CARS Facility. American Mineralogist, 85, 604607.CrossRefGoogle Scholar
Christy, A.G. and Grew, E.S. (2004) Synthesis of beryllian sapphirine in the system MgO-BeO-Al2O3-SiO2-H2O, and comparison with naturally occurring beryllian sapphirine and khmaralite Part 2: A chemographic study of Be content as a function of P, T and FeMg_j exchange. American Mineralogist, 89, 327338.CrossRefGoogle Scholar
Christy, A.G. and Mills, S.J. (2013) The effect of lone-pair stereoactivity on polyhedral volume and structural flexibility: application to TeIV-O octahedra. Acta Crystallographica, B69, 446456.Google Scholar
Christy, A.G., Tabira, Y, Holscher, A., Grew, E.S. and Schreyer, W. (2002) Synthesis of beryllian sapphirine in the system MgO-BeO-Al2O3-SiO2-H2O, and comparison with naturally occurring beryllian sapphirine and khmaralite Part 1: experiments, TEM and XRD. American Mineralogist, 87, 11041112.CrossRefGoogle Scholar
Christy, A.G., Mills, S.J., Kampf, A.R., Housley, R.M. Thorne, B. and Marty, I (2016) The relationship between mineral composition, crystal structure and paragenetic sequence: the case of secondary Te mineralization at the Bird Nest drift, Otto Mountain, California, USA. Mineralogical Magazine, 80,201—310.CrossRefGoogle Scholar
Frost, R.L. (2009) Tlapallite H6(Ca,Pb)2(Cu, Zn)3SO4(TeO3)4TeO6, a multi-anion mineral: a Raman spectroscopic study. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 72, 903906.CrossRefGoogle Scholar
Frost, R.L. and Keeffe, E.C. (2009) Raman spectroscopic study of kuranakhite PbMn4+Te6+O6 — a rare tellurate mineral. Journal of Raman Spectroscopy, 40, 249252.CrossRefGoogle Scholar
Grice, J.D. and Roberts, A.C. (1995) Frankhawthorneite, a unique HCP framework structure of a cupric tellurate. The Canadian Mineralogist, 33, 649653.Google Scholar
Grice, J.D., Groat, L.A. and Roberts, A.C. (1996) Jensenite, a cupric tellurate framework structure with two coordinations of copper. The Canadian Mineralogist, 34, 5559.Google Scholar
Hawthorne, F.C., Cooper, M.A. and Back, M.E. (2009) Khinite-4O [=khinite] and khinite-3T [=parakhinite]. The Canadian Mineralogist, 47, 473476.CrossRefGoogle Scholar
Housley, R.M., Kampf, A.R., Mills, S.J., Marty, I and Thorne, B. (2011) The remarkable occurrence of rare secondary tellurium minerals at Otto Mountain near Baker, California — including seven new species. Rocks and Minerals, 86, 132142.CrossRefGoogle Scholar
Kampf, A.R., Housley, R.M., Mills, S.J., Marty, I and Thorne, B. (2010a) Lead-tellurium oxysalts from Otto Mountain near Baker, California: I. Ottoite, Pb2TeO5, a new mineral with chains of tellurate octahedra. American Mineralogist, 95, 1329—1336.Google Scholar
Kampf, A.R., Marty, I and Thorne, B. (2010b) Lead-tellurium oxysalts from Otto Mountain near Baker, California: II. Housleyite, Pb6CuTe4O18(OH)2, a new mineral with Cu-Te octahedral sheets. American Mineralogist, 95, 13371342.CrossRefGoogle Scholar
Kampf, A.R., Housley, R.M. and Marty, I (2010c) Lead-tellurium oxysalts from Otto Mountain near Baker, California: III.Thorneite, Pb6(Te2O10)(CO3) Cl2(H2O), the first mineral with edge-sharing octahedral dimers. American Mineralogist, 95, 1548—1553.CrossRefGoogle Scholar
Kampf, A.R., Mills, S.J., Housley, R.M., Marty, I and Thorne, B. (2010d) Lead—tellurium oxysalts from Otto Mountain near Baker, California: IVMarkcooperite, Pb2(UO2)Te6+O6, the first natural uranyl tellurate. American Mineralogist, 95, 15541559.CrossRefGoogle Scholar
Kampf, A.R., Mills, S.J., Housley, R.M., Marty, I and Thorne, B. (2010e) Lead—tellurium oxysalts from Otto Mountain near Baker, California: V Timroseite, Pb2Cu52þ(Te6+O6)2(OH)2, and paratimroseite, Pb2Cu42þ(Te6+O6)2(H2O)2, new minerals with edge-sharing Cu—Te octahedral chains. American Mineralogist, 95, 15601568.CrossRefGoogle Scholar
Kampf, A.R., Mills, S.J., Housley, R.M., Marty, I and Thorne, B. (2010f) Lead-tellurium oxysalts from Otto Mountain near Baker, California: VI. Telluroperite, Pb3Te4+O4Cl2, the Te analogue of perite and nadorite. American Mineralogist, 95, 15691573.CrossRefGoogle Scholar
Kampf, A.R., Mills, S.J., Housley, R.M., Rumsey, M.S. and Spratt, I (2012) Lead—tellurium oxysalts from Otto Mountain near Baker, California: VII. Chromschieffelinite, Pb10Te6O20(OH)14(CrO4) (H2O)5, the chromate analogue of schieffelinite. American Mineralogist, 97,21 2—219.Google Scholar
Kampf, A.R., Mills, S.J., Housley, R.M. and Marty, I (2013a) Lead—tellurium oxysalts from Otto Mountain near Baker, California: VIII.Fuettererite, Pb3Cu2 +Te +O6(OH)7Cl5, a new mineral with double spango-lite-type sheets. American Mineralogist, 98, 506511.CrossRefGoogle Scholar
Kampf, A.R., Mills, S.J., Housley, R.M. and Marty, I (2013b) Lead-tellurium oxysalts from Otto Mountain near Baker, California: IX. Agaite, Pb3Cu2+Te6+O5(OH)2(CO3), a new mineral with CuO5-TeO6polyhedral sheets. American Mineralogist, 98, 512517.CrossRefGoogle Scholar
Kampf, A.R., Mills, S.J., Housley, R.M., Rossman, G.R., Marty, I and Thorne, B. (2013c) Lead-tellurium oxysalts from Otto Mountain near Baker, California: X. Bairdite, Pb2Cu4 +Te|+O10(OH)2(SO4)-H2O, anew mineral with thick HCP layers. American Mineralogist, 98, 13151321.CrossRefGoogle Scholar
Kampf, A.R., Mills, S.J. Housley, R.M., Rossman, G.R., Marty, J. and Thorne, B. (2013d) Lead-tellurium oxysalts from Otto Mountain near Baker, California: XI. Eckhardite, (Ca,Pb)Cu2+Te6+O5(H2O), a new mineral with HCP stair-step layers. American Mineralogist, 98, 16171623.CrossRefGoogle Scholar
Krivovichev, S.V. and Brown, I.D. (2001) Are the compressive effects of encapsulation an artifact of the bond valence parameters. Zeitschrift für Kristallographie, 216, 245247.Google Scholar
Mandarino, J.A. (2007) The Gladstone—Dale compatibility of minerals and its use in selecting mineral species for further study. The Canadian Mineralogist, 45, 13071324.CrossRefGoogle Scholar
Margison, S.M., Grice, J.D. and Groat, L.A. (1997) The crystal structure of leisingite, (Cu,Mg,Zn)2(Mg,Fe) TeO6'6H2O. The Canadian Mineralogist, 35, 759763.Google Scholar
Mills, S.J. and Christy, A.G. (2013) Revised values of the bond valence parameters for TeIV-O, TeVI-O and TeIV-Cl. Acta Crystallographica, B69, 145149.CrossRefGoogle Scholar
Mills, S.J., Christy, A.G., Kameda, T, Genin, J.-M.R.. and Colombo, F. (2012) Nomenclature of the hydrotalcite supergroup: natural layered double hydroxides. Mineralogical Magazine, 76, 12891336.CrossRefGoogle Scholar
Mills, S.J., Kampf, A.R., Christy, A.G., Housley, R.M., Rossman, G.R., Reynolds, R.E. and Marty, J. (2014) Bluebellite and mojaveite, two new minerals from the central Mojave Desert, California, USA. Mineralogical Magazine, 78, 13251340.CrossRefGoogle Scholar
Sheldrick, G.M. (2008) A short history of SHELX. Acta Crystallographica, A64, 112122.CrossRefGoogle Scholar