[meteorite-list] (no subject)
From: Mike Farmer <farmerm_at_meteoritecentral.com>
Date: Thu Apr 22 09:46:24 2004
Also the fact the NWA 073 is a porous L chondrite and Oum Rokba is a very solid
hard H chondrite. I find the the softer Ls tend to weather much faster.
Sandblasting in some areas can remove all traces of fusion crust, but leave a
meteorite little weathered, while one buried in sand or soil can retain it's
crust but be quite weathered.
> I wonder if you could help me regarding weathering grade...
> I have a couple of rocks that are weathering grade 2 (Oum Rokba) andMWA073
> with weathering grade 3.
> See pics below please!
> As you can see it apparently has a nice glossy (slightly worn) fusion crust.
> I don't have a pic of the Oum Rokba, but it has that finish that seems to be
> typical of all the other specimens I have seen.. It seems to have a classic
> desert varnish (ie no F/C) yet it's weathering grade is LOWER than the
> Am I misunderstanding the process of weathering grading?
> Thanks in anticipation for your erudite comments!
> In gentle decay,
> "I have a proof that x^n+y^n=z^n never has integer solutions for n>2.
> However, it won't fit into my signature file...."
> Meteorite-list mailing list
Received on Wed 16 May 2001 05:44:52 PM PDT