Large-scale calcium metal sample preparation for 41Ca isotope enrichment

Experiments are underway at Argonne National Laboratory to measure the 41Ca radioisotope concentration (T1/2 = 100 000 years) in natural samples of terrestrial origin by accelerator mass spectrometry (AMS). Since the concentration of 41Ca in these samples is expected to be very low, enrichment with a Calutron Isotope Separator at Oak Ridge National Laboratory is being used. This separator requires rather large quantities of high-purity Ca metal (typically 100 g/loading) as source material. Details of the methods of obtaining these metallic samples from various materials will be presented. (orig.)