Hostname: page-component-586b7cd67f-t8hqh Total loading time: 0 Render date: 2024-11-26T08:31:22.414Z Has data issue: false hasContentIssue false
  • English
  • Français

Biotites Intermediate Between Dioctahedral and Trioctahedral Micas

Published online by Cambridge University Press:  01 July 2024

J. Rimsaite
J. Rimsaite*
Affiliation:
Geological Survey of Canada, Ottawa, Canada
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Orange-yellow detrital flakes of biotite are common carriers of potassium and trace elements in soils and clays. Because the flakes differ in degree of alteration and may be derived from different sources, it is difficult to obtain homogeneous material for studies of their physical and chemical properties that may be compared with the original mica. A similar orange-yellow altered biotite occurs with fresh biotites in alkalie rocks of a nepheline deposit. The fresh and altered biotites were separated for chemical and minoralogical studies of the effects of weathering on biotite in its parent rock.

The common iron-rich biotites with octahedral occupancy between 5.5 and 5.8 alter to bright orange-yellow biotites with octahedral occupancy approaching five. These biotites, intermediate between the trioctahedral and dioctahedral micas, form as a result of oxidation during the process of their alteration to chlorite—vermiculite.

Biotites with octahedral occupancy approaching five were prepared experimentally by heating a natural biotite that contained high ferrous iron. The main differences between the natural and laboratory oxidized biotites are: the naturally oxidized micas lose 30% of the original potassium, adsorb about 2 wt.% water, and apparently gain about 25% hydroxyl, whereas laboratory oxidized micas retain potassium and lose hydroxyl and argon. The oxidized micas retain the crystal structure of the original mica.

Type
General
Information
Clays and Clay Minerals , Volume 15 , February 1967 , pp. 375 - 393
Copyright
Copyright © 1967, Springer International Publishing

References

Amirkhanoff, K. I., Brandt, S. V. and Bartinsκν, E. N. (1961) Radiogenic argon in minerals and its migration: Ann. N.Y. Acad. Sci. 91 (Art. 2), 235–75.CrossRefGoogle Scholar
Eberhart, J. P. (1963) Etude des transformations du mica muscovite par chauffage entre 700 et 1200°C: Bull. Soc. Franç. Minéral. 86, 213–51.Google Scholar
Eskola, P. (1936) On the disintegration of rapakivi: Bull. Commiss. Geol. Finlande 92, 96–105.Google Scholar
Eskola, P. (1949) The mica of the Moro: Bull. Commiss. Geol. Finlande 114, 113–16.Google Scholar
Goldschmidt, V. M. and Johnson, M. (1922) Glimmermineralernes betydning som kalikilde for planterne: Norges geol. Unders. 108, 89.Google Scholar
Grant, W. H. (1964) Chemical weathering of biotite-plagioclase gneiss: Clays and Clay Minerals, Proc. 12th Conf., Pergamon Press, New York, 455–63.Google Scholar
Karpinskaya, T. V., Ostrovskyi, I. A. and Shanin, L. L. (1961) Artificial instillation of argon into mica at high pressures and temperatures: Izvestya (Newsletter) Acad. Sci. U.S.S.R., Geol. Series, No. 8.Google Scholar
Porteous, P. E. and Gillie s on, A. H. (1966) Feasibility of quantitative determination of bonded hydroxyl in biotites by infrared spectroscopy: Dept. Mines Tech. Surveys, Mines Branch, Min. Sci. Div. Int. Rept. MS 66-29, 4 pp.Google Scholar
Ridgway, R. (1912) Color standards and nomenclature: Washington, D.C. (published by the author).CrossRefGoogle Scholar
Rimsaite, J. Y. H. (1963) Studies of rock-forming micas: Bull. Geol. Survey, Canada, 149 (in press).CrossRefGoogle Scholar
Rimsaite, J. (1964) On micas from magmatic and metamorphic rocks: Beitr. Min. Petrogr. 10, 152–88.Google Scholar
Smith, J. V. and Yoder, H. S., (1956) Experimental and theoretical study of the mica polymorphs: Min. Mag. 31, 209–34.Google Scholar
Tsvetkov, A. I. and Valyashikhina, E. P. (1956) Data on thermal studies of minerals: III Micas: Trans. Inst. Geol., Mining, Mineral Geochem., Ed. 4, Moscow, Acad. Sci. U.S.S.R.Google Scholar
Walker, G. F. (1949) The decomposition of biotite in the soil: Min. Mag. 28, 693–703.Google Scholar