Hi Pete, What about an LL -- with some desert weathering? The low-low metal can be converted to small Fe-oxides or veins.
I recently classified Northwest Africa 6588 (LL6-an), that had only trace amounts of Fe-Ni metal. The ubiquitous sulfides present are pendlandite and stoichiometric pyrite. See metsoc 2011 abstract: http://www.lpi.usra.edu/meetings/metsoc2011/pdf/5418.pdf Are you sure the sulfide is all troilite? Carl Agee -- Carl B. Agee Director and Curator, Institute of Meteoritics Professor, Earth and Planetary Sciences MSC03 2050 University of New Mexico Albuquerque NM 87131-1126 Tel: (505) 750-7172 Fax: (505) 277-3577 Email: [email protected] http://epswww.unm.edu/iom/pers/agee.html ------------------------------------------------------------- Message: 13 Date: Mon, 27 Jun 2011 00:31:45 -0400 From: Pete Pete <[email protected]> Subject: Re: [meteorite-list] Stones with High Troilite, Low Metal To: <[email protected]>, <[email protected]>, meteoritelist meteoritelist <[email protected]> Message-ID: <[email protected]> Content-Type: text/plain; charset="iso-8859-1" Thank you all for your responses. You're right, Doug, too ambiguous a question. I have an unclassified NWA, which I've sliced and polished. There are so many interesting features that it is the type that you never get tired of looking at under the microscope. It has what appears to be the remains of transformed chondrules; four total in about 2cm^2 surface. Three look like bit-remains of brecciated chondrules, grey and white. The other looks like a typical barred chondrule that has become completely crystallised, and has the schiller effect. A very fine grained matrix, no observable free metal as in nickel/iron, and what *appears* to be typical troilite scattered throughout. Low attraction to a neodymium magnet. The fusion crust is relatively fresh, with no chert. Quite different from the others I've got, so I was hoping to read and possibly view images of similar. As I said, there are no silver metal flecks, only the dull yellow troilite-looking areas. Is it possible for nickel/iron to have this appearance, too? I had mentally eliminated that due to the low magnet attraction, but I've got lots to learn. Cheers, Pete ______________________________________________ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list [email protected] http://six.pairlist.net/mailman/listinfo/meteorite-list
