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Wooldridgeite, Na2(P2O7)2(H2O)10: A new mineral from Judkins Quarry, Warwickshire, England

Published online by Cambridge University Press:  05 July 2018

F. C. Hawthorne ,
M. A. Cooper ,
D. I. Green ,
R. E. Starkey ,
A. C. Roberts  and
J. D. Grice
F. C. Hawthorne
Affiliation:
Department of Geological Sciences, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2
M. A. Cooper
Affiliation:
Department of Geological Sciences, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2
D. I. Green
Affiliation:
The Manchester Museum, University of Manchester, Oxford Road, Manchester M13 9PL, UK
R. E. Starkey
Affiliation:
15 Warwick Avenue, Bromsgrove, Worcestershire B60 2AH, UK
A. C. Roberts
Affiliation:
Geological Survery of Canada, 601 Booth Street, Ottawa, Ontario, Canada K1A 0E8
J. D. Grice
Affiliation:
Research Division, Canadian Museum of Nature, PO Box 3443, Station D, Ottawa, Ontario, Canada K1P 6P4
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Abstract

Wooldridgeite, ideally Na2(P2O7)2(H2O)10, orthorhombic, a = 11.938(1), b = 32.854(2), c = 11.017(1) Å , V = 4321.2(8) Å3, a:b:c = 0.3634:1:0.3353, space group Fdd2, Z = 8, is a new mineral from Judkins Quarry, Nuneaton, Warwickshire, England. Associated minerals are calcite, chalcopyrite, bornite and baryte. It occurs as equant crystals forming rhombic dipyramids; no twinning was observed. It is transparent blue-green with a very pale-blue streak, a vitreous lustre, and does not fluoresce under long- or short-wave ultraviolet light. Wooldridgeite has a Mohs hardness of 2–3, is brittle with an irregular fracture, and has no cleavage. The calculated density is 2.279 g/cm3. In transmitted light, wooldridgeite is colourless, non-pleochroic, and shows no dispersion. It is biaxial negative with α = 1.508(1), β = 1.511(1), γ = 1.517(1), 2V(meas.) = 76.2(5), 2V(calc.) = 71(10)8, X = b, Y = c, Z = a. The strongest five reflections in the X-ray powder diffraction pattern are [d(Å), (I), (hkl)]: 8.23(30)(040), 6.52(100)(131), 4.05(40)(260), 3.255(40)(262); 2.924(40)(371). Electron-microprobe analysis of wooldridgeite gave P2O5 39.37, CuO 20.24, MgO 0.24, CaO 7.73, Na2O 8.33, K2O 0.17, H2O(calc.) 24.72, sum 100.80 wt.%; the corresponding unit formula (based on 24 anions) is (Na1.96K0.03)Ca1.00(Cu1.85Mg0.04)P4.04O14(H2O)10 where the H2O groups were assigned from knowledge of the crystal structure; the infrared absorption spectrum also indicates the presence of H2O in the structure. The mineral is named for James Wooldridge (1923–1995), a fervent amateur mineral collector who discovered this mineral.

Keywords

wooldrigeitenew mineralpyrophosphateJudkins QuarryWarwickshireEngland
Type
Research Article
Information
Mineralogical Magazine , Volume 63 , Issue 1 , February 1999 , pp. 13 - 16
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1999

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References

Cooper, M.A. and Hawthorne, F.C. (1998) The crystal structure of wooldridgeite, Na2CaCu2 2+ (P2O7)2(H2O)10, a novel pyrophosphate structure. Canad. Mineral. (submitted).Google Scholar
Ince, F., Starkey, R.E. and Wooldridge, J. (1991) The geology and mineralogy of Judkins Quarry, Warwickshire. U.K.J. Mines Minerals, 10, 8–13.Google Scholar
Pouchou, J.L. and Pichoir, F. (1985) ‘PAP’ φ(ρZ) procedure for improved quantitative microanalysis. In Microbeam Analysis 1985, San Francisco Press, San Francisco, 104–60.Google Scholar
Roberts, A.C., Ercit, T.S., Criddle, A.J., Jones, G.C., Williams, R.S., Cureton, F.F. and Jensen, M.C. (1994) Mcalpineite, Cu3TeO6.H2O, a new mineral from the McAlpine mine, Tuolumne County, California, and from the Centennial Eureka mine, Juab County, Utah. Mineral. Mag., 58, 417–24.CrossRefGoogle Scholar