Dear List Members,

Reading the interesting infos about NBS-19 and other calcites I wonder if
anybody can give me information on the source of NIST SRM915a. This is the
official standard for calcium isotopes. Details on the chemical composition
are available from NIST, but there is no information what material it is
made from (limestone, marble, etc.). It has a very low 44Ca/40Ca
composition for a limestone.

Florian Boehm



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Florian Boehm
Leibniz-Institut f. Meereswissenschaften, IfM-GEOMAR
FB 2, Marine Biogeochemie/Ostufer
Wischhofstr. 1-3, D-24148 Kiel
Germany
email: [log in to unmask]
http://www.geomar.de/~fboehm/
Tel.: (49)431-600-2104
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