Hostname: page-component-586b7cd67f-t8hqh Total loading time: 0 Render date: 2024-11-24T23:49:18.606Z Has data issue: false hasContentIssue false
  • English
  • Français

Tristramite, a new calcium uranium phosphate of the rhabdophane group

Published online by Cambridge University Press:  05 July 2018

D. Atkin ,
I. R. Basham  and
J. F. W. Bowles
D. Atkin
Affiliation:
Geochemistry and Petrology Division, Institute of Geological Sciences, 64 Gray’s Inn Road, London WC1X 8NG
I. R. Basham
Affiliation:
Geochemistry and Petrology Division, Institute of Geological Sciences, 64 Gray’s Inn Road, London WC1X 8NG
J. F. W. Bowles
Affiliation:
Geochemistry and Petrology Division, Institute of Geological Sciences, 64 Gray’s Inn Road, London WC1X 8NG
Get access Rights & Permissions [Opens in a new window]

Abstract

Tristramite, a new mineral of the rhabdophane group, has the composition (Ca0.54U4+0.29Fe3+0.17)Σ1.00 [(PO4)0.79(SO4)0.12(CO3)0.07]Σ0.98·1.77H2O. It occurs as a late-stage replacement or matrix to brecciated uraninite (var. pitchblende) associated with sulphides in hydrothermal veins related to Hercynian granites in south-west England. It is hexagonal, space group P6222, with a 6.913 ± 0.003 Å and c 6.422 ± 0.006 Å. The strongest lines of the indexed powder pattern are 2.99 (100), 2.83 (100), 2.14 (50), 1.850 (50), 5.99 (40), 4.37 (40), 3.46 (30). For comparison, new indexed powder data for rhabdophane from Fowey Consols, Cornwall, are included. The mineral is pale yellow to greenish yellow, uniaxial positive with ω 1.644 and ε 1.664, and does not fluoresce in either short-or long-wave ultraviolet light. The habit is acicular or fibrous and no cleavage has been observed. Density (g/cm3) 3.8–4.2 (meas.), 4.18 (calc.).

Type
Research Article
Information
Mineralogical Magazine , Volume 47 , Issue 344 , September 1983 , pp. 393 - 396
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1984

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

Belova, L. N., Gorshkov, A. I., and Ivanova, O. A. (1978) Dokl. Akad. Nauk SSSR, Earth Sci. Sect. 238, 132–4.Google Scholar
Bowles, J. F. W. (1975) Rep. Inst. Geol. Sci. No. 75/9.Google Scholar
Boyle, D. R., Littlejohn, A. Roberts, A. C and Watson, D. M. (1981) Can. Mineral. 19, 325–31.Google Scholar
Dines, H. G. (1956) The metalliferous mining region of south-west England. 1, 240. Mem. Geol. Survey of Gt. Britain, London.Google Scholar
Fisher, F. G., and Meyrowitz, R. (1962) Am. Mineral. 47, 1346–55.Google Scholar
Kucha, H. (1979) Mineral. Polonica. 10, 3–25.Google Scholar
Mason, P. K., Frost, M. T., and Reed, S. J. B. (1969) B.M.-I.C.-N.P.L. computer programs for calculating corrections in quantitative X-ray microanalysis. Nat. Phys. Lab. (IMS), Rep. 2.Google Scholar
Mooney, R. C. L. (1950) Ada Crystallogr. 3, 337–40.CrossRefGoogle Scholar
Muto, T., Meyrowitz, R., Pommer, A. M., and Murano, T. (1959) Am. Mineral. 44, 633–50.Google Scholar
Smellie, J. A. T., Cogger, N., and Herrington, J. (1978) Chem. Geol. 22, 1–10.CrossRefGoogle Scholar
Soboleva, M. V., and Pudovkina, I. A. (1957) [Uranium Minerals Handbook, Moscow pp. 181–2]; abstr. in Am. Mineral. 43, 379–80, 1958.Google Scholar