>HELP!

Rob you have already been given the most relevant papers to help you with
the analyses of your "exotic" carbonates. If you have more than one
carbonate phase present and cant separate them easily the stepwise reaction
procedure of Al-Aasm (1990) is good. It is useful anyway to ensure that you
are reacting only one carbonate phase. Reacting dolomites, siderites etc.
at high temperatures for about an hour is the way to go (not weeks as in
days gone by) which is where the Rosenbaum and Sheppard (1986) paper is
required.  Rather than reacting samples and acid in a water bath at 100 oC
or building/buying a fancy heater I have found it a lot easier to use a
liquid paraffin bath instead (in a fume cupboard). Place the paraffin bath
(Pyrex) on a hot plate, turn up to required temp and wait for the bath
temperature to stablise. If you dont place too many reaction vessels in the
bath the temperature should not fluctuate. All this I have explained a
little better in  J. of Sedimentary Res. vol A65, 605-613.

Good luck.
Kevin