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A new interfacial method for conodont separation

Published online by Cambridge University Press:  19 May 2016

Zdzislaw Belka ,
Stanislaw Skompski  and
Boguslaw Waksmundzki
Zdzislaw Belka
Affiliation:
1Alexander von Humboldt Fellow, Geologisch–Paläontologisches Institut der Universität, Sigwartstrasse 10, D-7400 Tubingen, Federal Republic of Germany
Stanislaw Skompski
Affiliation:
2Institute of Geology, Warsaw University, Al. Zwirki i Wigury 93, 02-089 Warszawa, Poland
Boguslaw Waksmundzki
Affiliation:
2Institute of Geology, Warsaw University, Al. Zwirki i Wigury 93, 02-089 Warszawa, Poland
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Extract

Conodonts display higher specific gravity (2.84-3.10) than common minerals in sedimentary rocks. For several decades this property has been exploited to separate these microfossils from sediment residues using density separation techniques. Two heavy liquids commonly used, bromoform and tetra-bromoethane, are toxic (Sax, 1979; HaufTand Airey, 1980) and constitute a danger to human health. Tetrabromoethane is a known carcinogen (Brem et al., 1974). Both of these liquids should be abandoned in favor of nontoxic sodium polytungstate (Callahan, 1987; Merrill, 1987b; Krukowski, 1988). There are, however, some technical problems with its use because of relatively high viscosity and a tendency to recrystallize during separation. Another big disadvantage is also its price at $100 per kilogram. These problems may be considerably overcome by using polytungstate in the way described by Savage (1988).

Type
Paleontological Notes
Information
Journal of Paleontology , Volume 63 , Issue 2 , March 1989 , pp. 253 - 255
Copyright
Copyright © The Paleontological Society 

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References

Adamson, A. W. 1982. Physical Chemistry of Surfaces. John Wiley, New York, 664 p.Google Scholar
Brem, H., Stein, A. B., and Rosenkranz, H. S. 1974. The mutagenity and DNA-modifying effect of haloalkanes. Cancer Research, 34:2576–2579.Google ScholarPubMed
Callahan, J. 1987. A nontoxic heavy liquid and inexpensive filters for separation of mineral grains. Journal of Sedimentary Petrology, 57:765–766.CrossRefGoogle Scholar
Freeman, E. F. 1982. Fossil bone recovery from sediment residues by the “interfacial method.” Palaentology, 25:471–484.Google Scholar
Freeman, E. F. 1986. Recent progress in recovering micro vertebrate fossils using interfacial methods. Journal of Paleontology, 60:957–960.Google Scholar
Hauff, P. L., and Airey, J. 1980. The handling, hazards, and maintenance of heavy liquids in the geologic laboratory. U.S. Geological Survey Circular, 827:1–24Google Scholar
Krukowski, S. T. 1988. Sodium metatungstate: a new heavy mineral separation medium for the extraction of conodonts from insoluble residues. Journal of Paleontology, 62:314–316.CrossRefGoogle Scholar
Merrill, G. K. 1980. Removal of pyrite from microfossil samples by means of sodium hypochlorite. Journal of Paleontology, 54:633–634.Google Scholar
Merrill, G. K. 1985. Interfacial alternatives to the use of dangerous heavy liquids in micropaleontology. Journal of Paleontology, 59:479–481.Google Scholar
Merrill, G. K. 1987a. Improvements in interfacial methods for conodont separation, p. 55–63. In Austin, R. L. (ed.), Conodonts: Investigative Techniques and Applications. Ellis Horwood Ltd., Chichester.Google Scholar
Merrill, G. K. 1987b. Cryogenic density separation of conodonts, p. 63–66. In Austin, R. L. (ed.), Conodonts: Investigative Techniques and Applications. Ellis Horwood Ltd., Chichester.Google Scholar
Pokorny, V. 1963. Principles of Zoological Micropalaeontology. International Series of Monographs on Earth Sciences, Pergamon Press, Oxford, 652 p.Google Scholar
Savage, N. M. 1988. The use of sodium polytungstate for conodont separations. Journal of Micropalaeontology, 7:39–40.Google Scholar
Sax, N. I. 1979. Dangerous Properties of Industrial Materials, 5th ed.Van Nostrand Reinhold Co., New York, 1,118 p.Google Scholar
Stone, J. 1987. Review of investigative techniques used in the study of conodonts, p. 17–34. In Austin, R. L. (ed.), Conodonts: Investigative Techniques and Applications. Ellis Horwood Ltd., Chichester.Google Scholar
Stone, J., and Saunders, R. 1987. Magnetohydrostatic separation of conodonts from residues, p. 69–74. In Austin, R. L. (ed.), Conodonts: Investigative Techniques and Applications. Ellis Horwood Ltd., Chichester.Google Scholar
Then, D. R., and Dougherty, B. J. 1983. A new procedure for extracting foraminifera from indurated organic shale. Geological Survey of Canada, Paper 83-1B:413–414.Google Scholar
Varker, W. J. 1987. Electromagnetic separation of conodonts from residues, p. 67–69. In Austin, R. L. (ed.), Conodonts: Investigative Techniques and Applications. Ellis Horwood Ltd., Chichester.Google Scholar