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Monahans and sample curation

At 02:22 PM 6/11/98 -0700, you wrote:
>
>     Polling the List for non-aqueous rock cutting methods....
>     
>     I was refraining from asking this question - thought it might be 
>     considered a "newbie" question - but after reading posts about
hammers and 
>     thinking out loud comments like, "Oh yeah! Water and salt, good
point!", 
>     I'm getting a little nervous.
>     
>     Question - how do rare, one-of-a-kind stonies get cut?
>     
>     Let's continue this discussion about waterless rock cutting - 
>     Anybody out there have any suggestions?
>     How did NASA/JSC Houston cut/make their tests?
>     
>     Water, OUT - hammer, OUT - rock trimmer?
>     My experience with rock trimmers is that, how a rock breaks, is 
>     dependent upon the matrix.  Makes a difference whether the break goes 
>     through or around chondrules and crystals.
>     
>     My turn to think out loud - 
>     Since cutting fluids are used to primarily cool the blade, the problem 
>     is to find an appropriate replacement fluid.  If an air tight 
>     enclosure could be placed around the saw/blade, and the oxygen was 
>     replaced by another inert gas, would it be safe enough to use alcohol 
>     as a coolant?
>     
>     Educate me,
>     Bob V.

I'm going to answer the question about NASA directly, but also use this 
as a vehicle to do some preaching (mostly to the choir, I hope).

NASA/JSC goes to great lengths to avoid laboratory contamination of 
its Antarctic meteorites.  Virtually anything you do to a meteorite
has the potential to introduce terrestrial material into the meteorite,
or alter extraterrestrial minerals.  And it's not just mundane issues
like how to preserve halite crystals that you have to worry about.  We
can now do "ultra-low-level" analyses of chemical elements, isotopes,
organic constituents, etc., that require extraordinary care in the
handling of valuable meteorites specimens if meaningful results are
to be obtained.

The way I understand it, NASA/JSC people divide samples by mechanical 
methods, like gentle crushing or rock trimmers, or with unlubricated
saws for large specimens.  They have manufactured their own rock trimmer 
parts out of steel with known trace element content, and
have analyzed their saw blades as well.  They have even
studied the lubricants on moving parts of rock splitters as potential
contaminants.  They have looked at how paint on the laboratory walls 
may contribute to sample contamination. Samples are stored in nitrogen-
flushed cases. Thin sections of meteorites with water soluble minerals 
are prepared with organic solvents and lubricants (yes, water soluble 
minerals survive even in Antarctic meteorites). 

The result of NASA's methods is to produce specimens of the greatest
scientific usefulness, but sometimes of diminished aesthetic value (i.e.,
forget about nice, thin, parallel slices of a main mass that NASA could 
sell in the gift shop, God forbid).  

Obviously, this level of contamination control and care in sample
storage/handling is beyond the means of most people reading this list.
That's why, when an interesting and potentially scientifically
valuable specimen like Monahans (1998) comes along, it's really
important for the finders/collectors/dealers who obtain the specimen
to cooperate with research laboratories to make sure that at least a
reasonably sized piece is well-curated from a scientific standpoint.
One should not forget that the collectability and economic value
of meteorites are tied directly to their scientific value, which can
only be fully realized with proper scientific curation in a facility
that makes material freely available to researchers.

I'm sure that, in the case of Monahans (1998), many research labs would
be willing to assist in properly subdividing a specimen in exchange for
being allowed to keep and curate a small piece.  Deals like this are
clearly "win-win" situations for both collectors and scientists, and I
hope they can be a routine part of the discovery and initial-description
process of EVERY new meteorite that lands in private hands (so to speak).

jeff