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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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