NWA 12874 (1,392 g)

Northwest Africa 12874 (NWA 12874)
(Northwest Africa)
Purchased: 2019
Classification: Primitive achondrite (Winonaite)
History: The meteorite was purchased from a Morrocan meteorite dealer on the meteorite fair in Ensisheim, France.
Physical characteristics: Three dark brownish fragments with some fusion crust.
Petrography: The meteorite displays a recrystallized texture dominantly composed of typically 100 to 200 µm sized enstatite, forsteritic olivine, and augite grains, with enstatite being the most abundant mineral phase. Augite often contains low-Ca pyroxene exsolutions. 120 degree triple junctions are abundant. Minor phases include kamacite, schreibersite, and troilite. Contains veinlets of metal or Fe-oxide throughout. Neither feldspar nor chondrules were observed.
Geochemistry:
olivine: Fa3.3±0.1 (Fa3.2-3.4 FeO/MnO=15±1, n=13);
low-Ca pyroxene: Fs3.6±0.4Wo1.4±0.2 (Fs3.3-4.5Wo1.2-1.7, FeO/MnO=10±1, n=13);
Ca-pyroxene: Fs1.7±0.4Wo45.4±0.4 (Fs1.2-2.3Wo44.6-46.3, FeO/MnO=8±3, n=13);
feldspar: An11.5±0.3Ab83.5±0.6Or5.0±0.7, n=17
 
Place of purchase:
Ensisheim, France
Date:
P 2019
Mass (g):
192
Pieces:
3
Class:
Winonaite
Shock stage:
S1
Weathering grade:
W2
Fayalite (mol%):
3.3
Ferrosilite (mol%):
3.6; 1.7
Wollastonite (mol%):
1.4; 45.4
Magnetic suscept.:
4.75
Classifier:
A. Greshake, MNB
Type spec mass (g):
24.6
Type spec location:
MNB
Main mass:
Hanno Strufe
Comments:
Submitted by Ansgar Greshake