[meteorite-list] question: Tafassasset classification

From: Svend <Svend_at_meteoritecentral.com>
Date: Thu Apr 22 10:08:33 2004
Message-ID: <E17wmOx-0000Vs-00_at_smtp.web.de>

Hello Anne and list,

Sinve I recovered a small fragment from the Tafassasset strewfield I
have a few questions regarding the current research on this meteorite.
Our 9g Individual has been classified as "carbonaceous chondrite or
primitive achondrite (equilibrated CR-like meteorite)". A quite exotic
classification that in terms of nomenclature refers to the entry in
MAPS 37 (provisional announcement, p.19f.). In other papers Tafassasset
is usually discussed as "equilibrated CR-chondrite" or "CR-like
chondrite" or sometimes as "ungrouped CR-chondrite". J. Zipfel from the
MPI in Mainz says that refractory lithophiles fractionated compared to
a typical CR composition is leading to a possible classification as
primitive achondrite. Does anybody know about a final classification
yet?

Second question is TKW. In the first report in MAPS 37 the TKW is
discribed as 110kg. But I just came across an article by Anne Black in
Fusion Crust (march 02). (You should see the outstanding Tafassasset
specimen on her page!) She reports about recent analysis and the fact,
that some of the material recovered in fact turned out to be meteorites
of other petrologic types. As I intend to put an endcut of my recovered
individual on ebay any information about TKW and final classification
would be aprecciated.

Concerning colour and texture of Tafassasset I was surprised to see
that other specimen show a grey or light grey matrix. Except for the
many kamacite and martensite grains mine shows a dark almost black
matrix. If anybody in the list knows similar Tafassasset samples I
would be thankful for a post.

thanks all for your efforts
best wishes

Svend


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Received on Sat 28 Sep 2002 12:30:30 PM PDT