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Re: Meteorite Preservation

Jim,

Your summary of preservation techniques from ("The Care and Conservation
of Geological Material: Minerals, Rocks, Meteorites and Lunar Finds",
edited by Frank M. Howie) was of great interest to me as it is always a
worry on how to protect one's investment.   As well as maintaining the
specimens for posterity.

You  touched upon one issue that I have wondered about for quite some
time.  I have been reluctant to bring it forth to the list because of its
apparent controversial nature (as supported by your parenthetical
comment).  However, since it has appeared in an apparently reputable
source I would like to pursue this to get other list members reactions
and feedback.

The specific statement I'm referring to in you message is -
<<<"Cutting:
The book recommends cutting with a wire saw - a wire on a bandsaw  that
is coated with corundum. Mininises heat and lossage.
Another method is just to hit it with a stainless steel hammer! No loss,
not much damage. Honest, this was mentioned!">>>>

(Also, a year or two ago I read an article in Lapidary Journal in which
the author expressed "horror" at seeing a dealer break a meteorite slice
in two with his hands.)

While I would not support the use of a "stainless steel hammer" I have
often thought that controlled selective fracturing or cleaving with
appropriate instruments would be preferable to cutting.  (Obviously this
would not apply to irons - unless they are extremely weathered and have
developed cleavage lines of their own.)

The advantages for employing such an approach are -
1) No loss of material (As opposed to 10% to 25%, or more,  from cutting)
2) No heating (Eliminates potential for altering chemistry and structure)
3) No contaminants (Avoids use of cutting oils or water)
4) Reduces costs (Eliminates loss, time, equipment, materials)
5) Everyone wins (Except for those who like pretty things)

A while back another member of this list took a drubbing for fracturing
Zagami  into "specks".  This caused great concern and consternation for
many on the list and it is pointless to rehash its economic and business
merits.  My point in raising this is that there was no loss of material
through this technique.  How much Zagami has been lost - forever -
through cutting? 

It seems to me that cutting and polishing whole sections serves no
scientific purpose and is solely for esthetics.  (Polishing of small
windows of a specimen may be justified for thin section study or for
observing patterning, but why would it be necessary for every section to
be so treated?  I would appreciate any feedback on what practical
scientific purpose polishing serves.)

Lastly, I would appreciate hearing from anyone that has experimented with
preserving their specimens in a nitrogen or argon gas atmosphere.  I am
considering making a containment vessel for such purposes and would
appreciate any guidance anyone can provide.

These are just my thoughts, but given the exotic nature of this resource
it seems to me that every effort should be undertaken to preserve as much
of it, as possible, in its natural state.  I greatly appreciate any
comments anyone on the list would be willing to take the time to offer. 

Richard Kuzma

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