Improvements in TC/EA methodology for analysis of both sulfates and
nitrates is given in:

Böhlke, J. K., Mroczkowski, S. J., and Coplen, T. B., 2003, Oxygen isotopes
in nitrate: New reference materials for 18O:17O:16O measurements and
observations on nitrate-water equilibration: Rapid Communications in Mass
Spectrometry, v. 17, p. 1835-1846,

which should be out in mid July.  It presents delta O-18 values for both
sulfates and nitrates distributed by IAEA and NIST on a scale normalized to
VSMOW water = 0 per mill and SLAP reference water = -55.5 per mill.

The email address of the corresponding author is [log in to unmask]



                      Adam Porowski
                      <[log in to unmask]        To:       [log in to unmask]
                      .PL>                     cc:
                      Sent by: Stable          Subject:
                      Isotope
                      Geochemistry
                      <[log in to unmask]
                      UVM.EDU>


                      07/10/2003 02:44
                      AM
                      Please respond to
                      Stable Isotope
                      Geochemistry






Dear colleagues,

Could you please advise me some literature where I can find a description
of
methodology of sample preparation to measure stable isotopes of oxygen in
SO4--.
Any info will greatly appreciated.
Thanks.

#############################
Adam Porowski
Institute of Geological Sciences
Polish Academy of Sciences
ul. Twarda 51/55
00-818 Warsaw, POLAND
[log in to unmask]
tel: +48 22 697-87-56
fax: +48 22 620-62-23