Radioactivation analysis of "cosmic" and other magnetic spherules
Abstract
The published methods of the authors for the determination of cobalt, nickel, and copper by neutron activation analysis, have been used to determine trace quantities of these elements in "cosmic" and other magnetic spherules, in order to obtain quantitative evidence of their possible extra-terrestrial origin. Since the amount of spherules available for analysis ranged from ~10 to 250 μg only, special techniques, using a micro-manipulator for transferring the spherules to polythene strips for irradiation, had to be used, and these are described. The quantity of iron present was also determined by a spectro-photometric method. The nickel content of the spherules ranged from <0.03 to 3.9 μg, the cobalt from <0.01 to 0.3 μg, and the copper from 0.0006 to 0.53 μg. From the nickel/copper, nickel/cobalt, copper/cobalt, and nickel/iron ratios it is shown that two of the samples - those obtained from deep-sea cores - are closely similar to iron meteorites. In the case of the other two samples, one from the roof of a collecting station off the coast of Sweden, and the other separated from sand obtained from the River Danube, there is no correspondence in the above ratios, and they appear to be quite different in chemical composition from the spherules from deep-sea cores.
- Publication:
-
Geochimica et Cosmochimica Acta
- Pub Date:
- 1958
- DOI:
- 10.1016/0016-7037(58)90043-7
- Bibcode:
- 1958GeCoA..13..123S