[meteorite-list] Cornucopia of chondrules

From: Martin Goff <msgmeteorites_at_meteoritecentral.com>
Date: Tue, 11 Mar 2014 21:42:42 +0000
Message-ID: <CAKEL=tDj0DkCa0cGzhYPLuj6CsLWH1u-agkzGXyAuVSaXqD1qg_at_mail.gmail.com>

Thank you so much Bernd. This is where i show my ignorance! I will
have another look at this thin section tomorrow and get back to you
:-)

Cheers

Martin

On 11 March 2014 21:06, Bernd V. Pauli <bernd.pauli at paulinet.de> wrote:
> Martin writes:
>
> "I have now made an attempt to identify the different chondrules,
> hoping some folk with much more knowledge than me can chime in
> and correct my mistakes!"
>
> Hello Martin, Rob, and List,
>
> Martin, congrats on your colorful thin section photos! Well, colour is
> the problem I see myself faced with when looking at your thin section
> pics. They look almost too colourful. Are you sure the section has the
> proper thickness of 30?m (= 0.03 mm)?
>
> Here are my numbers for your thin section pics so you and the other
> list members know which pic I'm referring to:
>
> 1--2--3
> 4--5--6
> 7--8--9
> 10--11--12
> 13
>
> Now, #1 does look like an RP chondrule at first sight but if it is a radial
> pyroxene chondrule, the interference colours are too high. They should be first
> order, i.e., gray or grayish-white. Either the TS doesn't have the proper
> thickness or we are looking at something else: the high interference colors
> would speak in favour of a deformed (?) BO chondrule with slender bars.
>
> Chondrule #10: same problem! Provided the IF colours are correct, this
> is another BO chondrule. If it is an RP chondrule, the interference colours
> are wrong.
>
>
> My NWA 5730 has lots of metal-rimmed chondrules, FeNi is troilite-rimmed,
> porphyritic chondrules are abundant, numerous porphyritic chondrules harbor
> light-green translucent hypersthene crystals + a gray clayey-looking broken
> chondrule (d = 5.1 mm). I wonder if it is something carbonaceous or if it
> experienced some kind of silicate darkening.
>
> Best wishes from the owner of a 21.4 gr endcut that I got from Rob in 2011!
>
> Bernd
>
>
> ______________________________________________
>
> Visit the Archives at http://www.meteorite-list-archives.com
> Meteorite-list mailing list
> Meteorite-list at meteoritecentral.com
> http://six.pairlist.net/mailman/listinfo/meteorite-list

-- 
Martin Goff
www.msg-meteorites.co.uk
IMCA #3387

Received on Tue 11 Mar 2014 05:42:42 PM PDT