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Pseudo-pleochroic Calcite in Recrystallized Shell-Limestones

Published online by Cambridge University Press:  01 May 2009

J. D. Hudson
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Abstract

Limestones consisting of recrystallized shells of lamellibranchs, originally composed of aragonite, contain a brown-coloured calcite which is strongly pleochroic. Maximum “absorption’ corresponds to the extraordinary ray. The effect is shown to be a pseudo-pleochroism, caused by scattering of the extraordinary ray by inclusions, which follow the shell structure, in the calcite. Aragonite shells, which have not recrystallized, show a pseudo-pleochroism of similar colour but reversed sign. The inclusions originate in the conchiolin of the lamellibranch shell; their present nature is not known. Their progressive destruction by thermal metamorphism is described.

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Articles
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Geological Magazine , Volume 99 , Issue 6 , November 1962 , pp. 492 - 500
Copyright
Copyright © Cambridge University Press 1962

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References

REFERENCES

Abelson, P. H., 1959. Geochemistry of organic substances in Abelson, ed., Researches in Geochemistry. New York.Google Scholar
Anderson, F. W., 1948. Algal beds in the Great Estuarine Series of Skye. Proc. R. phys. Soc. Edinb., 23, 123–142.Google Scholar
Beedham, G. E., 1958. Observations on the non-Calcareous component of the shell of the Lamellibranchia. Quart. J. Micr. Sci., 99, 341–357.Google Scholar
Bøggild, O. B., 1930. The shell structure of the molluscs. K. danske vidensk. Selsk. Skr.Naturvidensk. Mathem. Afd., 9 Raekke, II. 2, 233–326.Google Scholar
Corin, F., 1931. Contribution à I'etude de la pseudo-absorption. Bull. Soc. franc. Minér, 54, 57–63.Google Scholar
Dimitrievitch, B., 1927. Sur un cas de pseudopolychroisme de la calcite- Bull. Soc. franc. Minér., 50, 501–504.Google Scholar
Federov, E. von., 1894. Üiber Pseudochroismus and Pseudodichroismus. Miner, petrogr. Mitt., 24, 569 (not seen; abstract in Z. Kristallogr., 27, 332).Google Scholar
Federov, E. von., 1900. Pseudoabsorption. Z. Kristallogr., 32, 11, 128.Google Scholar
Hudson, J. D., 1960. The Laig Gorge Beds, Isle of Eigg. Geol. Mag., 97, 313–322.CrossRefGoogle Scholar
Römer, O., 1903. Untersuchungen über den feineren Bau einiger Muschel-schalen. Z. wiss. Zool., 75, 437–472.Google Scholar
Schröder van der Kolk, J. L. C, 1900. Beiträge zur Kenntniss der Gesteine aus dem Molukken III Gesteine von Buru. Zbl. Miner. Geol. Palädont., for 1900, 373–374.Google Scholar
Vinogradov, A. P., 1953. The elementary chemical composition of marine organisms. Sears Found. Marine Research, Memoir 2, 1–647.Google Scholar
Wilbur, K. M., 1960. Shell structure and mineralization in molluscs, in Sognnaes, R. F., ed., Calcification in Biological Systems. Publ. Amer. Ass. Advanc. Sci., 64, 15–40.Google Scholar