[meteorite-list] Uncut NWA's - Does the exterior disclose

From: Matson, Robert <ROBERT.D.MATSON_at_meteoritecentral.com>
Date: Fri Jun 30 19:03:34 2006
Message-ID: <A8044CCD89B24B458AE36254DCA2BD07A4EBAC_at_0005-its-exmp01.us.saic.com>

Hi Walter,

> How do the finders, dealers etc, everyone but the poor collector, look
> at a batch of NWA's and decide which ones will be held on to and which
> ones end up on Ebay?

Magnetism, shape, texture and color.

> Does Doug look for something about the exterior that may indicate
> a clue to the "innards?"

But of course he does. ;-) If it's an obvious meteorite and yet has
very little (or no) attraction to a strong magnet, then it's probably
something interesting -- achondrite, LL, carbonaceous. Or, it could
just be an extremely weathered O.C. (though that would be rare for a
Sahara meteorite). Medium or strong paramagnetism: probably an H-
or L-chondrite, though enstatite chondrites can also be quite
attracted to magnets. (I'm assuming you'd have no difficulty
recognizing an iron.)

The crust of an achondrite does not look the same as the crust of
an ordinary chondrite or a carbonaceous chondrite. It's usually
glassier, blacker, or both. Bottom line is that "high-grading"
meteorites is not too difficult when you've got hundreds or
thousands to look through. --Rob
Received on Fri 30 Jun 2006 06:55:34 PM PDT