Activity Ratios in "Natural Uranium"

[Bobshann@aol.com]

I have recently had a request from a client regarding activity ratios in 
Natural Uranium.

Does anyone have any information regarding variation of the U-238:U-235 ratio 
in naturally occurring uranium in soils and ores?  

Likewise, does anyone know have any evidence for varying solubility of U-235 
relative to U-238 as has been documented in the literature for U-234 relative 
to U-238.

Thank you for any assistance you may be able to offer!

Bob Shannon
bobshann@aol.com
Paragon Analytics, Inc.
225 Commerce Drive
Ft Collins, CO 80524
800-443-1511	
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