[meteorite-list] THE taoudinid/ classification the biggest achondrite from NWA

From: habibi abdelaziz <azizhabibi_at_meteoritecentral.com>
Date: Sun, 23 Nov 2008 04:36:59 -0800 (PST)
Message-ID: <984894.60992.qm_at_web62006.mail.re1.yahoo.com>

HELLO ALL AGAIN,
an other clarification as many collector tought the taoudinid to be an earth rock , well this little asteroid is a meteorite here is an official classification. from sir dr albert jambon.
it's the biggest achondrite diogenite that went out of nwa and nea.
enjoy the photo

all the best
aziz habibi

http://www.flickr.com/photos/azizhabibi/sets/72157603629866992/comments/


Proposed Name Taoudeni NWA Geographic Coordinates : N 22?47.5? W3?58.0?

City, County, province/state and Country : Taoudeni, (Tombouctou),Mali.

Find : December 2007

Major classification (group)4 : Diogenite

 

History: A Moroccan meteorite hunter (Dhamen Ouled Ali) looking for pieces of Erg Chech fall , found by chance this 23 kg single stone, 15 km North of the Taoudeni salines.

Physical characteristics: One single stone, with patches of fusion crust (5 to 10 % approximately). TKW 24,370 g. log c = 2.8.

Petrography: A. Jambon, O. Boudouma, D. Badia ,UPVI. Study on one polished section by EMPA, SEM.

Cumulate texture of largely dominant orthopyroxene, with minor amounts of poikilitally enclosed olivine and chromite/pyrrhotite. Interstitial plagioclase and chromite. Rare silica and kamacite (mostly weathered) . A few clusters of subhedrehal olivine appear to be irregularly distributed (according to photographs of the whole stone). Millimetric crystals of gem quality. Mode from a BSE image on a polished section of about 2 cm2: Orthopyroxene = 87 %, Olivine = 7 %, Chromite = 1.6 %, Plagioclase = 3 %.

 

Mineral compositions and geochemistry: Abundant lo-Ca Pyroxene : En69Fs26Wo4; Cr2O3 = 0.7%; FeO/MnO = 31. Olivine Fa34; Cr2O3 = 0.03%, CaO = 0.08 %; FeO/MnO = 51. Minor hi-Ca Pyroxene: En45Fs13Wo42. Plagioclase An87Ab12Or1. Chromite : Mg# = 0.24; Cr/(Cr+Al) = 0.69. Kamacite with Ni = 12%.

 

Classification: Diogenite. Weathering : moderate. No shock features.

 

Type specimens: A specimen of 31 g and one polished section are on deposit at UPVI. A. Habibi (Erfoud) holds the main mass.


habibi aziz
www.palmserfoud.com
www.palmotel.com
box 70 erfoud 52200 morroco
phone. 21235576145
fax.21235576170



      
Received on Sun 23 Nov 2008 07:36:59 AM PST