[meteorite-list] Acfer breccia
From: Rob Lenssen <rlenssen_at_meteoritecentral.com>
Date: Wed, 17 Jan 2007 00:05:18 +0100 Message-ID: <001501c739c2$ca76a400$9600000a_at_EIGENAARNJEQJY> Thank you very much for your reaction Bernd. Like I wrote before, it was covered in desert varnish when I got it. The two polished planes present fractured sides, that I planed removing as less material as possible. Before planing they already showed dark "lumbs". Like it fractured "around them". Don't think it is planetary though, as it is magnetic and shows the typical (chondrite) dots of iron in the surface. I will try to make better pictures and will share them with you. regards, Rob ----- Original Message ----- From: <bernd.pauli at paulinet.de> To: <Meteorite-list at meteoritecentral.com> Sent: Tuesday, January 16, 2007 10:32 PM Subject: Re: [meteorite-list] Acfer breccia Hello Rob L. and List, Look what I found after cleaning and polishing a desert varnish covered Acfer: http://home.planet.nl/~rlenssen/Acfer500g.htm Dark clasts in lighter matrix. Also metal spots in the dark clasts. Any idea what this might be? In chondrites I typically see lighter clasts in darker matrix. What a beautiful A?fer chondrite! Is it a chondrite after all? The pictures should have a higher resolution. Are there any chondrules? Questions, questions, questions! Anyway, it does look quite fresh, so it should be something like W1 or W2 at most. It does look highly shocked ... at least S4 but more probably S5 or even S6. Well, that sounds like silicate darkening. Maybe the silicate clasts were not so very dark prior to the shock event but experienced extensive darkening (caused by melting of metal-sulfide). As for: "In chondrites I typically see lighter clasts in darker matrix" Here are some chondrites that have dark inclusions: NWA 0869, NWA 0978, NWA 1794, NWA 3346, OUED EL HADJAR, RICHFIELD, TANEZROUFT 061, etc., etc. Anyway, a mighty beautiful "chondrite", something that, as Dean would now say "you just gotta love!" ... and if it is not a chondrite ??? Could this be a planetary meteorite??? Questions, questions, questions! Cheers, Bernd To: rlenssen at planet.nl Meteorite-list at meteoritecentral.com ______________________________________________ Meteorite-list mailing list Meteorite-list at meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list Received on Tue 16 Jan 2007 06:05:18 PM PST |
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