[meteorite-list] NEW NAKHLITE / NWA 5790

From: Darryl Pitt <darryl_at_meteoritecentral.com>
Date: Wed, 14 Oct 2009 19:41:19 -0400
Message-ID: <449C16A4-0A93-42CA-B497-A31ECD356743_at_dof3.com>

And I'm happy to announce my gladly entertaining serious inquiries for
specimens of the same. ;-)




On Oct 14, 2009, at 7:07 PM, habibi abdelaziz wrote:

> hi all
> i m very happy to announce a very rare nakhlite has been discovred
> and classified,
> its nwa 5790 ;
>
> here is the classification and photo
>
> http://www.flickr.com/photos/azizhabibi/page3/
>
> thanks
> aziz habibi
>
> Proposed Name NWA 5790 Geographic Coordinates1
>
> City, County, province/state and Country Erfoud, Morocco
> Find: 2009
> Major classification (group) Martian (nakhlite)
>
>
>
> History: Found in the desert by nomads and purchased by A. Habibi in
> Erfoud.
> Physical characteristics: Two (136 + 9) g stones with millimetric
> phenocrysts in a groundmass with pinkish luster. Very friable.
> Petrography: (A. Jambon, O. Boudouma, D. Badia, UPVI )
> Millimetric euhedral dominant augite zoned over 10 micrormeter at
> the rim. Subsidiary euhedral olivine phenocrysts of similar size,
> zoned to their core. Intersitital mesostasis contains dendritic
> oxides pyroxene, feldspar, silica and glass. Mode from BSE images :
> Augite : 51.2, olivine 9.1, mesostasis 39.7, titanomagnetite <1%.
>
> Mineral compositions (SEM and EMPA; as above) and geochemistry (ICP-
> MS; J-A Barrat UBO): zoned augite core (En35?Fs24 Wo40 and Fe/Mn =
> 32) sharp rim (En20Fs43 Wo36 and Fe/Mn = 42), olivine progressively
> zoned from the core (Fa65 with Fe/Mn = 47) to the rim (Fa80 with Fe/
> Mn = 40). Rare Ti-magnetite phenocrysts Uv32Mt56Sp7Ct4 with fine
> ilmenite exsolutions.
> In the mesostasis dendritic crystals of Ti Magnetite :
> Uv52-74Mt38-19, acicular pyroxene (En7Fs47Wo46 and Fe/Mn = 55) and
> olivine Fa88. Plagioclase An16Ab79Or5;
>
> Bulk major-element chemistry similar to other nakhlites; element
> ratios confirm martian origin (K/La =473, Ga/Al =3.7 104);
> significantly higher proportion of mesostasis than other nakhlites
> with the highest Th, U and rare earth elements (REE) concentrations
> ever reported for a nakhlite ( e.g. , Th = 0.85 ppm); REE pattern
> characterized by a strong light REE enrichment (La/Yb)n =5.8, and Eu/
> Eu* = 0.86.
> Oxygen isotopes (R. Greenwood and I. Franchi, OU ): ?17 O = ?.
>
> Type specimens: A total sample mass of 20 g, are on deposit at
> UPVI ; main mass, Habibi .
>
> habibi aziz
> box 70 erfoud 52200 morroco
> phone. 21235576145
> fax.21235576170
>
>
>
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Received on Wed 14 Oct 2009 07:41:19 PM PDT