[meteorite-list] NWA 306 Thin Section Photos / Park Forest Winslow (under siding) Photos

From: MARK BOSTICK <thebigcollector_at_meteoritecentral.com>
Date: Sun Jul 25 18:15:56 2004
Message-ID: <BAY4-F10AwiXYIyhXMO000d4490_at_hotmail.com>

Hello Dean, Bernd and List,

Bernd wrote: "A few days ago I got a very nice NWA 306 thin section from
Dean. I am also glad that I was able to purchase a 10.2-gram NWA 306 endcut
from him - it is an extremely beautiful endcut with very fresh, black fusion
crust and an orange-colored matrix."

Congradulations on getting a nice....and fair priced...thin section.

"According to the Met.Bull. 86, 2002, it should be an L4, S2; W2 - but the
thin section looks more like an L5 (and this is what Dean actually offered
it as). Does anyone out there have any NWA 306 material and/or thin
sections? "

I have a one NWA 306 thin section. I just took several photographs of it
and placed it on a webpage.

http://www.meteoritearticles.com/colnwa306.html

"Could you /would you consider it an L4 or an L5. Also, the very fresh,
black fusion crust of my 10.2-gram specimen looks anything but not W2. I
would lean toward W1 or W0-1. Any opinions, any comments? Regards, Bernd"

When I at first looked over the thin section, I could not see many
consistant chondrules....which would have me lean towards the L5. However,
after a closer look the meteorite does have a lot of nice small chondrules
that are very consistant in size, ~.75mm. Also, there appears to be numous
olivine rich "pockets" that were chondrules at one point. While these are
"melted" I guess, the olivine is still pretty much in the same region it
originally was. It seems to me you see this less at the petrological
numbers get higher. My thin section section also shows several
comparitively large chondrules of pyroxene (~3-4mm)...but I guess you see
that in about all chondrites....especially the L class. So I am kind of
cross fence. I could see it fall under either classification.

Mark Bostick
www.meteoritearticles.com

PS: I have also added a few more Park Forest Winslow photographs that show
in more detail the under siding damage.

http://www.meteoritearticles.com/pfwinslowcrater.html
Received on Sun 25 Jul 2004 06:15:19 PM PDT