[meteorite-list] RFS Picture of the Day: Bassikounou

From: bernd.pauli at paulinet.de <bernd.pauli_at_meteoritecentral.com>
Date: 04 Oct 2007 15:24:35 UT
Message-ID: <DIIE.000000BC00002050_at_paulinet.de>

Hello Floyd, Dean, List,

Floyd "Griff" Griffith's Bassikounou - 252.8 grams is today's RFS
and a beautiful stone it is. Congratulations! You just gotta love this
stark contrast between the jet-black, pristine fusion crust and the
light- to medium-gray equally pristine interior of this fresh chondrite!

There is an absolutely fresh slice from Hanno Strufe in my collection.
It was one of the first to come out of Africa and its fusion crust is so
very fresh that you can spot unoxidized, silvery FeNi specks snugly
nestled into the fusion crust.

I recently added a "broken" individual that I purchased from Dean.
Thank you, Dean. It arrived today and it almost defies description.
Here it is:

http://www.meteoriteshop.com/metsale/Bassikounou.html

It's #24 and Dean describes it like that: "Bassikounou-39.3 Grams. One
of the best examples on any meteorite of primary and secondary crust."

And when he added in his private mail: "I can assure you that this is one
that you will really love. Nicer than my photo and when you see it you
really can see where it broke apart and then new crust started forming.
And the broken area is loaded with the greyest area ..."

..well, I thought that he was probably exaggerating a little. I was dead wrong!
The picture does *not* do it justice! Not only does it have a pitch-black
primary fusion crust but also three(!) kinds of secondary crust that reflect
different stages in the meteorite's descent and breakup:

1. one side shows a thick, black, dull coating of secondary crust
  totally covering the broken ripple-like surface beneath;

2. The downside displays a slightly thinner secondary fusion crust
  and looks like the warty, rear side of a flight-oriented meteorite.
  It is not oriented...I'm only trying to describe what it looks like.

3. The freshest secondary fusion crust can be seen where a piece
  must have broken off very late in its descent through the atmos-
  phere (lower left side in Dean's picture). Here I can see fusion
  crust in its incipient stage: small, feathery, black patches that
  look almost like fresh dentrites.

Dean, thank you so much for this one!

Best wishes and off to a PTA meeting!

Bernd
Received on Thu 04 Oct 2007 11:24:35 AM PDT