Dear Ethan and Dave:

The problem of anti-freeze is one of how easily it is removed from the
sample - thus solubility of anti-freeze and the porosity of the sample
must be considered.  Assuming that this is ethylene glycol - is it not
possible to remove this from the sample by solvents once cut ? I don't
recall in what this is soluble  - water, isopropyl or some other alcohol?

Also,  can't you drain the anti-freeze, clean the saw (thoroughly) and
fill it with water ? This would probalby take less time than the drive !
Particulate matter from previous cuttings should not be a problem unless
the pores (if there are any) fill with debris...repeated ultra-sonic
cleaning will help here.  

In addition, any samples that you take for stable isotope analysis
(powders) could/should be roasted (e.g., in vacuo at > 200 degrees C) to
remove whatever is left behind by the cutting, surface moisture,
and any fluid inclusions in the carbonate, etc.

Hope this helps.

Scott Carpenter
UT Dallas Geosciences


On Wed, 20 Nov 1996, Dave Wayne wrote:

> 
> Ethan,
> 
> My question to you is: Is the antifreeze recycled in the saw's cooling
> system? It probably is... in that case, the cut surface of your stalagmite
> would be contaminated with the C & O isotopic signature of the antifreeze,
> plus the C & O isotopic signatures of any tiny particles from previous
> samples cut in the saw prior to yours. You might alleviate the potential
> contamination from previous samples by making sure you use fresh antifreeze
> every time you cut your sample... otherwise, i would go ahead & make that
> long days' drive.
> 
> Dave Wayne
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>