Gray,

Take a look at the ISOGEOCHEM archives:

http://list.uvm.edu/cgi-
bin/wa?S2=isogeochem&q=dolomite&s=&f=&a=&b=

follow this link and look up contaminated calcite. That should give
you all the info you need on how to separate dolomite and calcite.

regards

Graham

>
>
> GRAY E. BEBOUT wrote:
>
> > Dear Colleagues,
> >
> >     I'd greatly appreciate a reminder of the older
> > references, but also ideas from the more recent
> > literature, direct experience, and gut-instinct, having
> > to do with the degree to which O-C-isotope compositions
> > of coexisting calcite and dolomite can be separately (and
> > quantitatively) analyzed via phosphoric acid dissolutions
> > (at different temperatures).  We're particularly
> > interested in obtaining O-C isotopic compositions of
> > calcite in rocks also containing varying, but small,
> > amounts of dolomite.


Graham Shields
Carleton-Ottawa Geoscience Centre
University of Ottawa
365 Nicholas Street
PO Box 450, Stn. A
Ottawa, Ontario
K1N 6N5
Canada
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