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Transformations of Micas in the Process of Kaolinitization of Granites and Gneisses

Published online by Cambridge University Press:  01 July 2024

Leszek Stoch  and
Wanda Sikora
Leszek Stoch
Affiliation:
Institute of Geology and Raw Materials, Academy of Mining and Metallurgy, Cracow, Poland
Wanda Sikora
Affiliation:
Institute of Geology and Raw Materials, Academy of Mining and Metallurgy, Cracow, Poland
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Abstract

Micas are described from the kaolin type Tertiary weathering crusts formed on granites and gneisses of Lower Silesia, Poland. In the weathering crust, large scale processes of transformation of micas (muscovite, biotite) take place. Weathering of micas is a gradual transformation of their structures by removal of the mobile cations Mg2+ Fe2+ Fe3+ and finally K +. Muscovite transforms into kaolinite through the intergrowths of two phases, mica and kaolinite. A degradation series, muscovite → mica/montmorillonite → montmorillonite → kaolinite also is observed. Biotite passes directly into kaolinite, but at higher concentrations of K and Al one observes the following sequence of biotite degradation: biotite → dioctahedral mica rich in Fe → dioctahedral mica poor in Fe → kaolinite. This process involves the exchange of Mg2+ and then Fe2+ of octahedral layers by Al3+ less mobile under weathering conditions. In the next stage of degradation, K + removal and kaolinite formation takes place. The micas representing different stages of this transformation, dark green, light-green, and silver-white, have been separated and investigated.

Type
Research Article
Information
Clays and Clay Minerals , Volume 24 , Issue 4 , August 1976 , pp. 156 - 162
Copyright
Copyright © 1976 The Clay Minerals Society

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References

Barany, R. (1964) Heat and free energy of formation of muscovite: U.S. Bur. Mines, Rep. Invest. 6356.Google Scholar
Barshad, I. and Kishk, J. M. (1968) Oxidation of ferrous iron in vermiculite and biotite alters fixation and replaceability of potassium: Science 162, 1401–1402.CrossRefGoogle ScholarPubMed
Budkiewicz, M. (1964) Złoza kaolinu w Polsce: Przegl. Geol. 12, 207–208.Google Scholar
Farmer, V. C., Russell, J. D., McHardy, W. J., Newman, A. C. D., Ahlichs, J. L. and Rimsaite, J. Y. H. (1971) Evidence for loss of protons and octahedral iron from oxidized biotites and vermiculites: Miner. Mag. 38, 121–137.CrossRefGoogle Scholar
Foster, M. D. (1960) Interpretation of the composition of trioctahedral micas: U.S. Geol. Surv. Prof. Papers 354-B, 11–49.CrossRefGoogle Scholar
Garrels, R. M. and Christ, Ch. L. (1965) Solutions, Minerals, Equilibria. Harper & Row, New York.Google Scholar
Garrels, R. M. and Howard, P. (1959) Reaction of feldspar and mica with water at low temperature and pressure: Clays & Clay Minerals 6, 68–88.Google Scholar
Ginzburg, I. I. (1963) Tipy drevnich kor vyvetrivanija 6. Izd. AN SSSR 71–101.Google Scholar
Hess, P. C. (1966) Phase equilibria of some minerals in the K2O-Na2O-Al2O3-SiO2-H2O system at 25°C and 1 atmosphere: Am. J. Sci. 264, 289–309.CrossRefGoogle Scholar
Konta, J., Borovec, Z., Šramek, J. and Tolar, Vl. (1972) Changes of primary biotite and muscovite during kaolinization of granites, Carlsbad Area, Czechoslovakia: 5th Conf. Clay Miner. Petrol. pp. 27–43. Praha 1970.Google Scholar
Kukovsky, E. G. (1969) Alteration processes in clay minerals: Clay Miner. 8, 234–237.CrossRefGoogle Scholar
Leonard, R. A. and Weed, S. B. (1970) Effect of potassium removal on the b-dimension of phlogopite: Clays & Clay Minerals 18, 197–202.CrossRefGoogle Scholar
Petrov, V. P. (1967) Osnovy učenija o drevnich korach vyvetrivanija. Nedra, Moskva.Google Scholar
Reesman, A. L. and Keller, W. D. (1968) Aqueous solubility studies of high-alumina and clay minerals: Am. Miner. 53, 929–942.Google Scholar
Rossini, F. D., Wagman, D. D., Ewans, W. A., Jaffe, J. and Levine, S. (1952) Selected values of chemical thermodynamic properties: U.S. Nat. Bur. Stand. Circ. 500.Google Scholar
Sikora, W. and Stoch, L. (1972) Mineral forming processes in weathering crusts of acid magmatic and metamorphic rocks of Lower Silesia: Mineralogia Polonica 3, 39–52.Google Scholar
Stoch, L. (1960) Intergrowth of kaolinite and muscovite in clays from Bolesławiec region, Lower Silesia: Bull. Acad. Pol. Sci., sér. sci. géol. géogr. 8, 21–29.Google Scholar
Tardy, Y. (1971) Characterization of the principal weathering types by the geochemistry of waters from some European and African crystalline massifs: Chem. Geol. 7, 253–276.CrossRefGoogle Scholar
Taylor, H. F. W. (1960) Aspects of the crystal structures of calcium silicates and aluminates: J. appl. Chem. 10, 317–323.CrossRefGoogle Scholar