![]() |
||
|
Northwest Africa 13790 | |||||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Basic information | Name: Northwest Africa 13790 This is an OFFICIAL meteorite name. Abbreviation: NWA 13790 Observed fall: No Year found: 2020 Country: (Northwest Africa) Mass: ![]() | ||||||||||||||||||||||||||||||
Classification history: |
This is 1 of 80 approved meteorites (plus 1 unapproved name) classified as Winonaite. [show all] Search for other: Primitive achondrites, Winonaites | ||||||||||||||||||||||||||||||
Comments: | Approved 28 Mar 2021 | ||||||||||||||||||||||||||||||
Writeup![]() |
Writeup from MB 110:
Northwest Africa 13790 (NWA 13790) (Northwest Africa) Purchased: 2020 Nov Classification: Primitive achondrite (Winonaite) Physical characteristics: Some fragments have fusion crust. The main mass is 131.4 g. Petrography: (K. Metzler, IfP) Coarse-grained mafic rock, consisting of olivine (~45 vol%), low-Ca pyroxene (~10 vol%), Ca-rich pyroxene (~20 vol%), plagioclase (~10 vol%), Fe-Ni metal (~15 vol%), and small amounts of troilite. Olivine grains with reverse chemical zoning (Mg-rich reduction rims) occur. Metal occurs as isolated grains and as veins up to several cm in length. The rock shows a metamorphic texture with frequent 120° triple junctions at crystal boundaries and partly poikilitic intergrowths. Typical grain sizes vary between 100 and 500 µm. However, cm-sized areas of olivine and pyroxene, respectively, show identical optical orientation. Geochemistry: Mineral compositions and geochemistry: The mean olivine composition is Fa3.4±0.6 (Fa2.0-4.1; n=15); Fe/Mn (at.): 15.8. The mean low-Ca pyroxene composition is Fs4.4±0.3Wo1.9±0.2 (Fs3.9-5.0Wo1.6-2.2; n=15); Fe/Mn (at.): 12.6. The mean composition of Ca-rich pyroxene is Fs1.3±0.3Wo43.8±0.6 (Fs0.9-2.2Wo42.9-45.1; n=15); Fe/Mn (at.): 10.7. The mean feldspar composition is An20.9±0.7Or3.0±0.5 (An19.9-22.1Or2.1-3.8; n=10). Classification: Winonaite, based on the mineral chemistry and the high abundance and shape of Fe-Ni metal. | ||||||||||||||||||||||||||||||
Data from: MB110 Table 0 Line 0: |
|
||||||||||||||||||||||||||||||
Institutions and collections |
IfP: Institut für Planetologie, Wilhelm-Klemm-Str. 10, 48149 Münster, Germany (institutional address; updated 23 Jan 2012) |
||||||||||||||||||||||||||||||
Catalogs: |
| ||||||||||||||||||||||||||||||
References: | Published in Gattacceca J., McCubbin F.M., Grossman J., Bouvier A., Chabot N.L., D'Orazio M., Goodrich C., Greshake A., Gross J., Komatsu M., Miao B., and Schrader D. (2022) The Meteoritical Bulletin, No. 110. Meteorit. Planet. Sci. 1-4
| ||||||||||||||||||||||||||||||
Photos: |
| ||||||||||||||||||||||||||||||
Geography: |
Statistics: This is 1 of 9116 approved meteorites from (Northwest Africa) (plus 1873 unapproved names) |