Dear Albert,

the IAEA intercomparison distribute NBS-127 (BaSO4 precipitated from
seawater) has been analyzed by several laboratories for its
oxygen isotope composition which is around +9.5 %. vs. V-SMOW. Contact
Manfred Groening from IAEA Vienna for an aliqout.

Cheers
Michael

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Dr. Michael E. Boettcher
Institute of Chemistry and Biology of the Marine Environment (ICBM)
Carl von Ossietzky University
P.O. Box 2503
D-26111 Oldenburg
FRG
Voice: +0441-798-2534   (office)
                -3403   (isotope lab)
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