Hostname: page-component-cd9895bd7-gxg78 Total loading time: 0 Render date: 2024-12-27T22:55:05.909Z Has data issue: false hasContentIssue false

Zinc- and Y-group-bearing senaite from St Peters Dome, and new data on senaite from Dattas, Minas Gerais, Brazil

Published online by Cambridge University Press:  05 July 2018

Eugene E. Foord
Affiliation:
US Geological Survey, Denver Federal Center, Denver, Colorado 80225, USA
William N. Sharp
Affiliation:
US Geological Survey, Denver Federal Center, Denver, Colorado 80225, USA
John W. Adams
Affiliation:
705 Garland Street, Lakewood, Colorado 80215, USA

Abstract

A Zn- and Y-group-bearing senaite, formulated as AM21O38 (Pb0.63Na0.46Ba0.11)Σ1.20(Ti14.64Zn1.74Y‒group REE0.70Mn0.38Nb0.20Sn0.03Zr0.03Th0.02)Σ20.9O38, a member of the crichtonite group, is a newly characterized phase associated with murataite at the St Peters Dome area, Colorado. The Zn- and Y-group-bearing senaite is uranium-free and nonmetamict, but otherwise is comparable to known senaites and davidites in X-ray diffraction pattern, symmetry, and structure. The REE distribution shows a strong dominance of Y and the Y-group REE which are present in M(1). Megascopically, the mineral is black, submetallic, and opaque; in polished section it appears to be white and moderately bright compared with murataite. Cleavage is absent but twinning on {520} is present.

Senaite and hitherto unreported zinc-bearing senaite from Dattas, Diamantina, Minas Gerais, Brazil, have the following respective structural formulas as determined by electron microprobe:

(Pb0.76Sr0.20La0.08Ce0.07Ba0.04)Σ1.15(Ti12.89Mn0.88Y0.59Zn0.12Mg0.07Nb0.03Cr0.02Th0.02)Σ20.61O38

and

(Pb0.89Ba0.15Ce0.02Sr0.02)Σ1.08(Ti14.57Zn1.76Na0.63Mn0.50Y0.28Nb0.14Mg0.04Cr0.02)Σ20.83O38

Type
Research Article
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

Ablanov, B. F. (1966) Geol. Geokhim. Mineral. Mestorozh. Tsvet. Metall. Kazakhstana, 152–7.Google Scholar
Adams, J. W., Botinelly, T, Sharp, W. N., and Robinson K. (1974) Am. Mineral. 59, 172–6.Google Scholar
Arribas, A. (1963) Estud. Geol. Inst. ‘Lucas Mallada'. 19, 33–51.Google Scholar
Barker, F., Wones, D. R., Sharp, W. N., and Desborough, G. A. (1975) Precamb. Res. 2, 97–160.CrossRefGoogle Scholar
Butler, J. R. (1961) Econ. Geol. 56, 442–3.Google Scholar
Butler, J. R. and Hall, R. (1960) Ibid. 1541, 50.Google Scholar
Campbell, I. H., and Kelly, P. R. (1978) Mineral. Mag. 42, 187–93.CrossRefGoogle Scholar
Davydova, L. I., and Shaposhnikov, G. N. (1966) Zap. Vses. Mineral. Obsh. 95, 474–6.Google Scholar
Dixon, P., and Wylie, A. W. (1951) Nature. 167, 526.CrossRefGoogle Scholar
Fleischer, M. (1983) Glossary of Mineral Species 1983. Mineral. Record, Tucson, Arizona.Google Scholar
Gatehouse, B. M., Grey, I. E., Campbell, I. H., and Kelly, P. (1978) Am. Mineral. 63, 28–36.Google Scholar
Gatehouse, B. M. and Kelly, P. R. (1979) Ibid. 1010, 17.Google Scholar
Grey, I. E. and Lloyd, D. J. (1976) Ada Crystallogr. B32, 13.Google Scholar
Grey, I. E. and Gatehouse, B. M. (1978) Can. Mineral. 16, 63–8.Google Scholar
Grey, I. E., Lloyd, D. J., and White, J. S. Jr., (1976) Am. Mineral. 61, 1203–12.Google Scholar
Gross, E. B., and Heinrich, E. W. (1966) Ibid. 299, 323.Google Scholar
Hanson, G. N. (1978) Earth. Planet. Sci. Lett. 38, 26–43.CrossRefGoogle Scholar
Hayton, J. D. (1960) Econ. Geol. 55, 1030–8.CrossRefGoogle Scholar
Hussak, E., and Prior, G. T. (1898) Mineral. Mag. 12, 30–2.Google Scholar
Kelly, P. R., Campbell, I. H., Grey, I. E., and Gatehouse, B. M. (1979) Can. Mineral. 17, 635–8.Google Scholar
MacDonald, R., and Saunders, M. J. (1973) Mineral. Mag. 39, 97111.CrossRefGoogle Scholar
Mawson, D. (1906) Trans. R. Soc. S. Austral. 30, 188–93.Google Scholar
Neumann, H., and Sverdrup, T. L. (1960) Nor. geol. Tidsskr. 40, 277–88.Google Scholar
Pabst, A. (1961) Am. Mineral. 46, 700–18.Google Scholar
Portnov, A. M., Nikolayeva, L. E., and Stolyarova, T. I. (1966) Dokl. Akad. Nauk SSSR. 166, 1420–1.Google Scholar
Rouse, R. C., and Peacor, D. R. (1968) Am. Mineral. 53, 869–79.Google Scholar
Sarp, H., Bertrand, J., Deferne, J., and Liebich, B. W. (1981) Neues Jahrb. Mineral. Mh. 433–42.Google Scholar
Shabin, A. G., Voronkov, A. A., Khalezova, E. B., and Kazakova, M. E. (1963) Trudy Inst. Mineral. Geokhim. Kristallokhim. Redk. Elem. 15, 110–21.Google Scholar
Smellie, J. A. T., Cogger, N, and Herrington, J. (1978) Chem. Geol. 22, 1–10.CrossRefGoogle Scholar
Van Wambeke, L. (1968) Mineral. Deposita. 3, 178–81.CrossRefGoogle Scholar
Vujanovic, V. (1970) Institut za Geologsko-Rudarska Istrazivanja i Ispitivanja Nukleamih i Drugih Mineralnih Sirovina. 5, 148–55.(in Serbian).Google Scholar
Welin, E., and Uytenbogaardt (1963) Arkiv. Mineral. Geol. 3, 277–92.Google Scholar
Whittle, A. W. G. (1959) Econ. Geol. 54, 64–81.CrossRefGoogle Scholar