![]() |
||
|
Northwest Africa 15857 | |||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Basic information | Name: Northwest Africa 15857 This is an OFFICIAL meteorite name. Abbreviation: NWA 15857 Observed fall: No Year found: 2021 Country: (Northwest Africa) Mass: ![]() | ||||||||||||||||||||||||||||
Classification history: |
This is 1 of 81 approved meteorites classified as Aubrite. [show all] Search for other: Achondrites, Aubrites, Enstatite achondrites, and Enstatite-rich meteorites | ||||||||||||||||||||||||||||
Comments: | Approved 15 Oct 2023 | ||||||||||||||||||||||||||||
Writeup![]() |
Writeup from MB 112:
Northwest Africa 15857 (NWA 15857) (Northwest Africa) Purchased: July 2021 Classification: Enstatite achondrite (Aubrite) History: Purchased in July 2021 by Geologist Juan Avilés Poblador, Roger Jones, and Sean Mahoney from a meteorite dealer in south Morocco. Physical characteristics: Many grayish to grayish-white pieces and fragments (some contain orange-colored spots due to weathering). Some fragments contain minor fusion crust, others contain a network of dark shock melt veins on their surfaces. Petrography: (D. Sheikh, Cascadia) Specimen represents a coarse-grained breccia comprised of strongly shocked mm to cm-sized enstatite grains (some containing inclusions of diopside) set within a matrix containing dark shock melt veins. Accessory phases identified include Ti-bearing troilite, daubréelite, and Si-bearing kamacite. Forsterite and plagioclase were not observed in the section analyzed. Geochemistry: Enstatite (Fs0.1±0.1Wo0.5±0.2, range Fs0.1-0.2Wo0.4-0.8, n=15), Diopside (Fs0.1±0.1Wo43.9±2.6, range Fs0.1-0.2Wo42.1-45.8, n=3). Classification: Achondrite (Aubrite) Specimens: 20.5 g at Cascadia, main mass with Sean Mahoney (200 g), Geologist Juan Avilés Poblador (350 g), and Roger Jones (250 g). | ||||||||||||||||||||||||||||
Data from: MB112 Table 0 Line 0: |
|
||||||||||||||||||||||||||||
Institutions and collections |
Cascadia: Cascadia Meteorite Laboratory, Portland State University, Department of Geology, Room 17 Cramer Hall, 1721 SW Broadway, Portland, OR 97201, United States; Website (institutional address; updated 28 Oct 2011) |
||||||||||||||||||||||||||||
Catalogs: |
| ||||||||||||||||||||||||||||
References: | Published in Meteoritical Bulletin, no. 112, in preparation (2023)
| ||||||||||||||||||||||||||||
Geography: |
Statistics: This is 1 of 9429 approved meteorites from (Northwest Africa) (plus 1876 unapproved names) |