Hostname: page-component-5c6d5d7d68-sv6ng Total loading time: 0 Render date: 2024-08-20T10:05:19.274Z Has data issue: false hasContentIssue false

The Oxidation of Octahedral Iron in Biotite

Published online by Cambridge University Press:  01 July 2024

R. J. Gilkes
Affiliation:
Department of Soil Science and Plant Nutrition, Institute of Agriculture, University of Western Australia, Nedlands, Western Australia 6009
R. C. Young
Affiliation:
Department of Soil Science and Plant Nutrition, Institute of Agriculture, University of Western Australia, Nedlands, Western Australia 6009
J. P. Quirk
Affiliation:
Department of Soil Science and Plant Nutrition, Institute of Agriculture, University of Western Australia, Nedlands, Western Australia 6009

Abstract

Oxidation of octahedral ferrous iron in biotite by saturated bromine water results in a loss of both octahedral and interlayer cations. The hydroxyl adjacent to vacant octahedral cation sites adopt an inclined orientation resulting in a more stable environment for interlayer cations. The only structural change accompanying these processes is a decrease in b-axis dimension which is linearly related to octahedral ferric iron content. These findings are in agreement with observations made on naturally weathered biotites.

Résumé

Résumé

L’oxydation du fer ferreux octaédrique de la biotite par l’eau de brome saturée entraîne à la fois une perte de cations octaédriques et interfeuillets. L’hydroxyle adjacent au site cationique octaédrique vacant adopte une orientation inclinée entraînant un environnement plus stable pour les cations interfeuillets. Le seul changement de structure qui accompagne ces phénomènes est une diminution du paramètre b qui est relié linéairement à la teneur en fer ferrique octaédrique. Ces observations sont en accord avec celles que l’on peut faire sur les biotites altérées naturellement.

Kurzreferat

Kurzreferat

Die Oxydation von oktaedrischem Ferro-Eisen in Biotit durch gesättigtes Bromwasser ergibt einen Verlust an oktaedrischen sowie zwischenschichtigen Kationen. Die, freien oktaedrischen Kationenstellen benachbarten, Hydroxyle nehmen eine geneigte Richtung ein wodurch sich eine stabilere Umgebung für Zwischenschichtkationen ergibt. Der einzige, diese Vorgänge begleitende, Gefügewechsel ist eine Abnahme der b-Achsendimension, die in linearer Beziehung zu dem oktaedrischen Ferri-Eisengehalt steht. Diese Befunde stimmen überein mit Beobachtungen, die an natürlich verwitterten Biotiten gemacht wurden.

Резюме

Резюме

Окисление октаэдрического железистого иона в биотите посредством насыщенной бромом водой, ведет к потере как октаэдрических так и межслоевых катионов. Гидроксил рядом с незаполненными октаэдрическими местонахождениями катионов принимают наклонную ориентацию в результате чего получается более стабильная среда для прослоенных катионов. Единственное структурное изменение сопровождающее эти процессы является уменьшение размера оси-b, линейно связанной с октаэдрическим содержанием железа. Эти данные совпадают с наблюдениями над естественно выветренными биотитами.

Type
Research Article
Copyright
Copyright © Clay Minerals Society 1972

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

Arnold, P. W., (1960) Nature and mode of weathering of soil-potassium reserves J. Sci. Food Agric. 11 285292.CrossRefGoogle Scholar
Barshad, I., (1966) The effect of the variation in precipitation on the nature of clay mineral formation in soils of acid and basic igneous rocks Proc. Internat. Clay Conf. Israel Jerusalem.Google Scholar
Barshad, I. and Kishk, F. M., (1968) Oxidation of ferrous iron in vermiculite and biotite alters fixation and replaceability of potassium Science 162 14011402.CrossRefGoogle ScholarPubMed
Brindley, G. W. and MacEwan, D. M. C., (1953) Structural aspects of the mineralogy of clays Ceramics—A Symposium Stoke-on-Trent The British Ceramic Society 1559.Google Scholar
Brown, G., (1965) Significance of recent structure determinations of layer silicates for clay studies Clay Miner. 6 7383.CrossRefGoogle Scholar
Denison, I. A., Fry, W. H. and Gile, P. L., (1929) Tech. Bull. U.S. Dep. Agric. .Google Scholar
Dyakonov, Yu. S. and L’Vova, I. A., (1967) Transformation of trioctahedral micas into vermiculite Doklady Akad. Nauk. SSSR 175 432434.Google Scholar
Farmer, V. C. and Russell, J. D., (1964) The i.r. spectra of layer silicates Spectrochim. Acta 20 11491173.CrossRefGoogle Scholar
Farmer, V. C., Russell, J. D. and Ahlrichs, J. L., (1968) Spectroscopy of clay minerals Trans. 9th Int. Congr. Soil Sci. Adelaide, Australia 3 101110.Google Scholar
Farmer, V. C. and Wilson, M. J., (1970) Experimental Conversion of biotite to hydrobiotite Nature 226 841842.CrossRefGoogle ScholarPubMed
Farmer, V. C., Russell, J. D., McHardy, W. J., Newman, A. C. D. Ahlrichs, J. L. and Rimsaite, J. Y. H., (1971) Evidence for loss of protons and octahedral iron from oxidised biotites and vermiculites Miner. Mag. 38 121137.CrossRefGoogle Scholar
Foster, M. D. (1960) Interpretation of the composition of trioctahedral micas’. U.S. Geol. Surv. Profess. Paper 354-B.Google Scholar
Gastuche, M. C., (1963) Kinetics of acid dissolution of biotite Proc. Int. Clay Conf. Stockholm 6783.Google Scholar
Gilkes, R. J., Young, R. C. and Quirk, J. P., (1972) Oxidation of ferrous iron in biotite Nature 236 8991.Google Scholar
Ismail, F. T., (1969) Role of ferrous iron oxidation in the alteration of biotite Am. Mineralogist 54 14601466.Google Scholar
Jackson, M. L. and Bear, F. E., (1964) Chemical composition of soils Chemistry of the Sod New York Reinhold.Google Scholar
Juo, A. S. R. and White, J. L., (1969) Orientation of the dipole moments of hydroxyl groups in oxidised and unoxidised biotite Science 165 804805.CrossRefGoogle Scholar
Radaslovich, E. W., (1962) The cell dimensions and symmetry of layer lattice silicates Am. Mineralogist 47 617636.Google Scholar
Raussel-Colom, J. A., Sweatman, T. R., Wells, C. B. and Norrish, K. (1965) In Experimental Pedology (Edited by Hallsworth, E. G. and Crawford, D. V.), Butterworth, London.Google Scholar
Rimsaite, J., (1970) Structural formulae of oxidised and hydroxyl-deficient micas and decomposition of the hydroxyl group Contr. Min. Petrol. 25 225240.CrossRefGoogle Scholar
Robert, M. and Pedro, G., (1969) Etude des relations entre les phenomenes d’oxydation et l’aptitude a 1’ouverture dans les micas trioctaedriques Proc. Int. Clay Conf. Japan. .Google Scholar
Rouxhet, P. G., (1970) Hydroxyl stretching bands in micas: a quantitative interpretation Clay Miner. 8 375388.CrossRefGoogle Scholar
Serratosa, J. M. and Bradley, W. F., (1958) I.R. absorption of OH bonds in micas Nature 181 111112.CrossRefGoogle Scholar
Vedder, W., (1964) Correlations between i.r. spectrum and chemical composition of mica Am. Mineralogist 49 736768.Google Scholar
Walker, G. F., (1949) The decomposition of biotite in the soil Miner. Mag. 28 693703.Google Scholar