[meteorite-list] D'Orbigny, Unusual Angrite, Thin Section Photographs

From: MARK BOSTICK <thebigcollector_at_meteoritecentral.com>
Date: Wed May 11 12:32:52 2005
Message-ID: <BAY104-F38F0959A02D8DC153A871FB3100_at_phx.gbl>

Hello list,

(Forgive me for if any of the following is scientifically wrong, this is my
observations paired with my at times limited knowledge.)

I recently received a D'Orbigny thin section. Which I have placed several
photographs of on my web site at the following web page.

http://www.meteoritearticles.com/coldorbigneyts.html

One the best thin sections I have. OK, move over NWA 998, it is the best.
This is due to its prismatic augite crystals, often found twisted with
olivine, randomly placed anorthite shards, and the many large vugs/vug
inclusions, in the stone. Some of these are filled with olivine or glass,
some are empty and some are hollow, meaning the show traces of the former.
In one vug on my thin section, is a well formed specter shaped crystal
sticking out. In my microscope it appears bright red, so perhaps it is
olivine. Another interesting note on the crystal that it formed in a hollow
vug. Meaning in a vug that has traces of the former minerals that once
filled the vug. This would mean of course that it formed after whatever was
in the vug, which is most likely olivine. This is all my amateur observation
and if anyone thinks the crystal, seen in photo 7, is not olivine, let me
know your opinion please. Also photo 7 and photo 11, shows particle bugs
with, under cross polars, appears brown as shown. This is what I think are
hollow vugs, as described in a couple of papers. The former mineral thing
again. Empty vug walls are shown in photos 7 and 8.

Opinions and thoughts welcomed,

Clear Skies,
Mark Bostick
Wichita, Kansas
http://www.meteoritearticles.com
http://www.kansasmeteoritesociety.com
http://www.imca.cc

http://stores.ebay.com/meteoritearticles
Received on Wed 11 May 2005 12:32:48 PM PDT