Dear Weihong:

My two cents worth:

You didn't tell us if these are natural mineral samples or precipitates 
from groundwater.

I prepare BaCO3 precipitates from water off line for the following 
reasons.  If you know the sulfate/carbonate content  you can easily 
calculate how much material to weigh out--either for combustion in an 
EA or for acidification--if the material is dry.  However, I worry 
about absorption of atmospheric CO2 due to the high residual pH in the 
system--whether dry or in a wet slurry.

As a result, I try to minimize contact time with atmosphere during all 
stages of handling.  I  load a standard two-legged reaction vessel with 
slurry, dry it under vacuum, acidify it, and run it by dual inlet.

I'm sure others will have other views.

On May 14, 2006, at 7:13 AM, CAT CAT wrote:

> Hello,
>  
> I have a question here:
>  
> Have any of you ever analyzed BaCO3 in your autoanalyzer? Is this 
> possible and
> what are the constraints if any that you know of? Thanks.
>  
> Have a nice day.
> Weihong
>
> Talk is cheap. Use Yahoo! Messenger to make PC-to-Phone calls. Great 
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-- 
*************************************************************
Steve Nelson
Associate Professor
Dept. of Geological Sciences
S-389 ESC
Brigham Young University
Provo, UT  84602

801-422-8688

"Guns don't kill people, Dick Cheney kills people."
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