[meteorite-list] a question on fusion crust

From: Michael Murray <mmurray_at_meteoritecentral.com>
Date: Wed, 21 Mar 2007 18:20:52 -0600
Message-ID: <B81844BB-FE42-493C-B6E8-366E4A95C2C7_at_montrose.net>

Hi List,
Are you ready for a dumb question! Here goes... Is there a more
definitive description of the blackened outer layer on the surface of
iron meteorites than simply referring to it as "fusion crust"? From
what I can gather looking at different pictures of stonys, they seem
to have a glassy or melted layer of the material of the stone. I can
see that being a 'crust'. On at least some irons, there is a coating
but it doesn't appear glassy, just blackened. I'm guessing that
that coating is partially resulting from burning of the gases in the
atmosphere? If it is a 'crust', it is not much of one. It looks
like a very thin coating of soot that is adhered to the stone,
although more durable than soot. This is probably one of those dumb
questions that the Collection of Wisdom would answer.

The stone in this picture has the blackened layer I'm referring to:

<http://i127.photobucket.com/albums/p124/mmurray_02/IMG_0319.jpg>

Michael Murray
Received on Wed 21 Mar 2007 08:20:52 PM PDT