I apologize in advance for this general posting to the isogeochem list.

Last summer there was an ongoing discourse regarding the calibration and
precision of delta 18O and delta 13C measurements generated from biogenic
carbonates.  At the time, I tossed in my two cents and mentioned that NBS16
and NBS-17, both CO2 gas standards for calibrating CO2 reference gas
directly, were no longer available.  Somebody from within the US goverment
(perhaps NIST or the USGS I don't recall) on this list piped in that they
were in the process of replacing these CO2 standards.  I recently
downloaded the SRM 1996 price list and couldn't find them, nor have I
received an answer to my e-mail query to NIST.  Since I inadvertently
deleted the original message I have lost the address of the person who
responded and hence am reverting to this form of broad-based communication.

Does anybody have information regarding either NIST or IAEA CO2 gas standards?

Please don't clutter the list as I have done -  cut and past my email address!


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