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Crimsonite, PbFe3+2(PO4)2(OH)2, the phosphate analogue of carminite from the Silver Coin mine, Valmy, Nevada, USA

Published online by Cambridge University Press:  02 January 2018

A. R. Kampf ,
P. M. Adams ,
S. J. Mills  and
B. P. Nash
A. R. Kampf*
Affiliation:
Mineral Sciences Department, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, Los Angeles, CA 90007, USA
P. M. Adams
Affiliation:
126 South Helberta Avenue #2, Redondo Beach, California 90277, USA
S. J. Mills
Affiliation:
Geosciences, Museum Victoria, GPO Box 666, Melbourne 3001, Victoria, Australia
B. P. Nash
Affiliation:
Department of Geology and Geophysics, University of Utah, Salt Lake City, UT 84112, USA
*
*E-mail: [email protected]
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Abstract

Crimsonite (IMA2014-095), PbFe3+2(PO 4)2(OH)2, the phosphate analogue of carminite, is a new mineral from the Silver Coin mine, Valmy, Iron Point district, Humboldt County, Nevada, USA, where it occurs as a low-temperature secondary mineral in association with fluorwavellite, goethite, hematite, hentschelite, plumbogummite and variscite on quartz. Crimsonite occurs in subparallel aggregates of deep red blades or plates flattened on {100} and up to 0.1 mm in maximum dimension. The streak is light purplish orange. Crystals are transparent and have adamantine lustre. The Mohs hardness is ∼3½, the tenacity is brittle, the fracture is irregular to splintery and an imperfect cleavage is likely on {101}. The calculated density is 5.180 g/cm3. Crimsonite is optically biaxial (+), with 2V = 85.5(5)° and γ – α = 0.011. Using the Gladstone-Dale relationship, the calculated indices of refraction are α = 2.021, β = 2.026 and γ = 2.032. The optical orientation is X = b; Y = a; Z = c and the pleochroism is X light orange, Y light yellow, Z red brown; Y < X < Z. Electron microprobe analyses provided PbO 40.69, CaO 0.60, ZnO 0.72, CuO 0.13, Fe2O3 23.36, Al2O3 0.34, V2O5 0.70, As2O5 12.05, P2O5 16.03, SO3 0.33 and H2O 3.64 (structure), total 98.59 wt.%. The empirical formula (based on 10 O apfu) is (Pb1.06Ca0.06)∑1.12(Fe1.71Zn0.05Al0.04Cu0.01)∑1.81(P1.32As0.61V0.05S0.02)∑2.00O8[(OH)1.64(H2O)0.36]∑2.00. Crimsonite is orthorhombic, Cccm, a = 16.2535(13), b = 7.4724(4), c = 12.1533(9) Å, V = 1476.04(17) Å3 and Z = 8. The eight strongest lines in the powder X-ray diffraction pattern are [dobs in Å(I)(hkl)]: 5.86(42)(111); 4.53(45)(112); 3.485(64)(113); 3.190(100) (022); 3.026(40)(004); 2.902(54)(511); 2.502(77)(422) and 2.268(54)(224). The structure of crimsonite (R1 = 3.57% for 740 Fo > 4σF) contains FeO6 octahedra that share edges to form dimers, which are then linked to other dimers by corner sharing to form chains along [010]. These chains are linked by PO4 tetrahedra yielding sheets parallel to {001}. The sheets are linked to one another via bonds to 8-coordinated Pb2+ atoms with non-stereoactive 6s2 lone-electron pairs.

Keywords

crimsonitenew mineralcrystal structurecarminiteSilver Coin mineValmyNevadaUSA
Type
Research Article
Information
Mineralogical Magazine , Volume 80 , Issue 6 , October 2016 , pp. 925 - 935
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2016

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References

Adams, P.A., Wise, W.S. and Kampf, A.R. (2015) The Silver Coin mine, Iron Point district, Humboldt County, Nevada. Mineralogical Record, 46, 701—728.Google Scholar
Brese, N.E. and O'Keeffe, M. (1991) Bond-valence parameters for solids. Acta Crystallographica, B47, 192—197.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, 244–247.CrossRefGoogle Scholar
Chukanov, N.V., Pekov, I.Y., Mockel, S., Zadov, A.E. and Dubinchuk, V.T. (2006) Zinclipscombite ZnFe32 (PO4)2(OH)2 - a new mineral. Proceedings of the Russian Mineralogical Society, 135, 13—18.Google Scholar
Gunter, M.E., Bandli, B.R., Bloss, F.D., Evans, S.H., Su, S.C. and Weaver, R (2004) Results from a McCrone spindle stage short course, a new version of EXCALIBR, and how to build a spindle stage. The Microscope, 52, 23–39.Google Scholar
Higashi, T., (2001) ABSCOR.Rigaku Corporation, Tokyo.Google Scholar
Kampf, A.R., Adams, P.M., Kolitsch, U. and Steele, I.M. (2009) Meurigite-Na, a new species, and the relationship between phosphofibrite and meurigite. American Mineralogist, 94, 720–727.CrossRefGoogle Scholar
Kampf, A.R., Adams, P.M., Housley, R.M. and Rossman, G.R. (2014) Fluorowardite, NaAl3(PO4)2F2(OH)2(H2O)2, the fluorine analogue of wardite from the Silver Coin mine, Valmy, Nevada. American Mineralogist, 98, 804–810.CrossRefGoogle Scholar
Kampf, A.R., Adams, P.M., Mills, S.J. and Nash, B.P. (2015a) Crimsonite, IMA 2014-095. CNMNC Newsletter No. 24, April 2015, page 249. Mineralogical Magazine, 79, 247—251.Google Scholar
Kampf, A.R., Adams, P.M., Nash, B.P. and Marty, J. (2015b) Ferribushmakinite, Pb2Fe3+(PO4)(VO4)(OH), the Fe3+ analogue of bushmakinite from the Silver Coin mine, Valmy, Nevada. Mineralogical Magazine, 79, 661–669.CrossRefGoogle Scholar
Kampf, A.R., Adams, P.M., Barwood, H. and Nash, B.P. (2015c) Fluorwavellite, IMA 2015-077. CNMNC Newsletter No. 28, December 2015, page 1862. Mineralogical Magazine, 79, 1859–1864.Google Scholar
Keller, P. (1977) Paragenesis: Assemblages sequences, associations. Mineralogical Record, 8, 38–7. [Special issue: Tsumeb! The world's greatest mineral locality (W.E. Wilson, editor)]Google Scholar
Kharisun, , Taylor, M.R., Bevan, D.J.M.. and Pring, A. (1996) The crystal structure of carminite: refinement and bond valence calculations. Mineralogical Magazine, 60, 805–811.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, 245–247.Google Scholar
Mandarino, J.A. (1981) The Gladstone-Dale relationship: Part IV The compatibility concept and its application. The Canadian Mineralogist, 19, 441—450.Google Scholar
Mills, S.J., Kampf, A.R., Sejkora, J., Adams, P.M., Birch, W.D. and Plášil, J. (2011) Iangreyite: anew secondary phosphate mineral closely related to perhamite. Mineralogical Magazine, 75, 329—338.CrossRefGoogle Scholar
Mills, S.J., Sejkora, J., Kampf, A.R., Grey, I.E., Bastow, T.J., Ball, N.A., Adams, P.M., Raudsepp, M. and Cooper, M.A. (2012) Krásnoite, the fluorophosphate analogue of perhamite, from the Huber open pit, Czech Republic and the Silver Coin mine, Nevada. Mineralogical Magazine, 76, 625—634.CrossRefGoogle Scholar
Pouchou, J.-L. and Pichoir, F. (1991) Quantitative analysis of homogeneous or stratified microvolumes applying the model “PAP.” Pp. 3l-75 in: Electron Probe Quantitation, (K.F.J. Heinrich and D.E. Newbury, editors). Plenum Press New York.Google Scholar
Pring, A., Birch, W.D., Dawe, J.R., Taylor, M.R., Deliens, M. and Walenta, K. (1995) Kintoreite, PbFe3(PO4)2(OH,H2 O)6, a new mineral of the jarosite-alunite family, and lusungite discredited. Mineralogical Magazine, 59 143–148.CrossRefGoogle Scholar
Roberts, A.C., Cooper, M.A., Hawthorne, F.C., Criddle, A.J. and Stirling, J.A.R.. (2002) Sewardite, CaFe3þ 2 (AsO4)2(OH)2, the Ca-analogue of carminite, from Tsumeb, Namibia: description and crystal structure. The Canadian Mineralogist, 40 1191–1198.CrossRefGoogle Scholar
Sheldrick, G.M. (2008) A short history of SHELX. Acta Crystallographica, A64 112–122.CrossRefGoogle Scholar
Thomssen, D. and Wise, W.S. (2004) Special list: Silver Coin Mine, Iron Point district, Edna Mountains, Humboldt Co., Nevada, USA. International Micromounter’s Journal, 13, 7–8.Google Scholar