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Vochtenite, (Fe2+,Mg)Fe3+[UO2/PO4]4(OH). 12–13 H2O, a new uranyl phosphate mineral from Wheal Basset, Redruth, Cornwall, England

Published online by Cambridge University Press:  05 July 2018

P. C. Zwaan ,
C. E. S. Arps  and
E. de Grave
P. C. Zwaan
Affiliation:
Rijksmuseum van Geologie en Mineralogie, Hooglandse Kerkgracht 17, 2312 HS Leiden, The Netherlands
C. E. S. Arps
Affiliation:
Rijksmuseum van Geologie en Mineralogie, Hooglandse Kerkgracht 17, 2312 HS Leiden, The Netherlands
E. de Grave
Affiliation:
Laboratorium voor Magnetisme, Rijksuniversiteit Gent, Proeftuinstraat 42, 9000 Gent, Belgium
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Abstract

Vochtenite, a new mineral from the Basset Mine, southeast of Camborne in Cornwall, England, is a ferrous-ferric magnesium-bearing hydroxy uranyl phosphate mineral. It is monoclinic with a = 12.606, b = 19.990, c = 9.990 Å, β = 102.31° Z = 3; the ideal formula is:

The strongest lines in the X-ray powder diffraction pattern are: 9.998(100)(020), 4.999(30)(040), 4.892(45)(002), 3.475(70)(311), 3.333(50)(060), 3.087(40)(232), and . Vochtenite is brown in colour with a bronzy lustre and is non-fluorescent. Mohs hardness is 2.5 and the density (calc.) = 3.663 g/cm3. There is a prominent (010) cleavage. Vochtenite is optical biaxial negative, 2V (calc.) = 89(3)° its dispersion is indiscernible. Refractive indices are α = 1.575(2), β = 1.589(2), γ = 1.603(2), and the pleochroism is very weak. Orientation X(α)∥b is perpendicular to (010) and Z(γ)∧c is small. The mineral occurs as subparallel (0.5–1.0 mm) crystal aggregates with a pseudo-quadratic outline. The mineral is named vochtenite after Prof. Dr. Ing. R. F. C. Vochten of the State University of Antwerpen, Belgium.

Keywords

vochtenitenew mineraluranyl phosphate groupWheal BassetCornwallEngland
Type
Mineralogy
Information
Mineralogical Magazine , Volume 53 , Issue 372 , September 1989 , pp. 473 - 478
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1989

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References

Brink, G. (1972) Infrared studies of water in crystalline hydrates. Spectrochimica Acta 28A, 1151-5.CrossRefGoogle Scholar
Fowler, B. O. (1974a) Infrared studies of apatites: I Vibrational assignments for calcium, strontium and barium hydroxylapatites utilizing isotopic substitution. lnorg. Chem. 13, 194-207.CrossRefGoogle Scholar
Fowler, B. O. (1974b) Infrared studies of apatites: II Preparation of normal and isotopically substituted calcium, strontium and barium hydroxylapatites and spectra-structure-composition. Ibid. 13, 207-14.CrossRefGoogle Scholar
Fowler, B. O., Moreno, E. C. and Brown, W. E. (1966) Infrared spectra of hydroxylapatite, octacalcium phosphate and pyrolysed octacalcium phosphate. Arch. Oral. Biol. 11, 477-92.CrossRefGoogle Scholar
George, D'Arcy (1949) Mineralogy of uranium and thorium bearing minerals. US Atomic Energy Comm. RMO-563. Tech. Inf. Service Extension, Oak Ridge, Tenn.Google Scholar
Gonzalez-Dias, P. F. and Santas, M. (1978) Infrared spectra of strontium, lead and barium apatites. Spectrochimica A cta 34A, 241-6.CrossRefGoogle Scholar
Ichida, K., Kuroda, Y., Nakamura, D. and Kubo, M. (1972) Vibrational spectral of water molecules in some transition metal dichloride dihydrates. Ibid 28A, 2433-41.Google Scholar
McMasters, O. D. and Larsen, W. L. (1964) Determination of the crystallographic lattice type and cell constants from X-ray powder pattern data, a computer program. US Atomic Energy Commission Report IS-839.Google Scholar
Maltese, M. and Orville-Thomas, W. J. (1967) The infrared spectra and structure of some complex hydroxosalts. J. Inorg. nucl. Chem. 29, 2533-44.CrossRefGoogle Scholar
Mandarino, J. A. (1981) The Gladstone-Dale relationship: Part IV. The compatibility concept and its application. Can. Mineral. 19, 441-50.Google Scholar
Palmer, M. and Neaversen, P. (1987) The Basset Mines: their history and industrial archaeology. Monogr. Northern Mine Research Society. British Mining No. 32.Google Scholar
Visser, J. W. (1969) Fully automatic program for finding the unit cell from powder data. J. Appl. Spect. 2, 89-95.Google Scholar
Vochten, R. F. C., de Grave, E. and Pelsmaekers, J. (1984) Mineralogical study of bassetite in relation to its oxidation. Am. Mineral. 69, 967-78.Google Scholar