TASSA MAHCHI
Sahara 03500

Achondrite, anom.
discovered 2003 Sahara.

One of the strangest meteorite ever found !

TKW 221.33 g

A single 221.33 g stone weighing was discovered by a Caillou Noir team prospecting for meteorites in the Sahara.

A 21 g end cut was given to Université Pierre & Marie Curie ( UMPC ) Jussieu, Paris, France, for analyses.
A 2.0 g part slice was given to University of Clermont Ferrand for similar purposes.

Main mass
221.33 g
Full ultra thin Slice 6.66 g
70 * 46* 1 mm
Metallic exsolution in Sulfur.

Macroscopic aspect: Rock covered with a nice cracked fusion crust (dark brown greenish) with centimetric protrubering metallic clasts and a deep regmaglypt on one side, broken on the other side with desert alteration. A fine grained light gray-green rock containing dark globules with rusty rim of a few cm to mm (about 16 vol %).
Petrography and mineralogy: Highly fractured rock with interstitial glass. Glomerocrysts of pyroxene: core En77Fs20Wo3; rim En50Fs14Wo36 Olivine slightly zoned (Fo 81 to Fo 76). Interstitial glass with ± feldspathic composition( about Ab17An4Or13Qz65) Globules of pyrrhotite (up to cm) with dendritic exsolution of metal visible with the naked eye. Small globules (<500 mm) of kamacite surrounded by pyrrhotite. Discontinuous rim of schreibersite. Inside globule exsolution of taenite as thin ribbons oriented close to the globule wall. Exsolved schreibersite inside the globule. Some secondary veins (terrestrial alteration) of Ca-carbonate.
Specimens: UPMC: 21.36 g, Université de Clermont III: . Analyses A. Jambon ,O Boudouma (UPMC) and B. Devouard (U. Clermont). 2.00 g.
Main mass: Caillou Noir.

More details: download the Clermont Ferrand University Powerpoint file click here
Look also at Sahara 03505 on this site or in Met Bul. 91.

 

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