Northwest Africa 18237 Basic information Name: Northwest Africa 18237 This is an OFFICIAL meteorite name. Abbreviation: NWA 18237 Observed fall: No Year found: 2024 Country: Mali Mass:help 484 g Classification history: Recommended: Ureilite [explanation] This is 1 of 720 approved meteorites classified as Ureilite. [show all] Search for other: Achondrites, Ureilites Comments: Approved 6 Dec 2025 Writeuphelp Writeup from MB 114: Northwest Africa 18237 (NWA 18237) Mali Find: 2024 Classification: Ureilite History: A single sample weighing 484 g was found in the Bir Ounane region of Mali by Hameti Mrabih in 2024. Physical characteristics: The sample is rounded and brown exterior exhibiting orientation. Small patches of fusion crust are present on specimen The cut face has a protogranular and poikiloblastic texture composed of elongate grains that form a foliation. Petrography: Description and classification (A. Love, App) Sample shows cumulate texture composed of equant to elongated -mm-sized olivine and pigeonite. Olivine and some pigeonite show metal bearing reduced margins at grain boundaries and fractures. Some grains show curvilinear trails of rounded troilite blebs. Additional minerals are: troilite, rare chromite and graphite. Geochemistry: (A. Love, App) Olivine (Cores: Fa22.0±0.4, Fe/Mn=46.6±3.2, Cr2O3=0.6±0.0, CaO=0.3±0.0, n=14; rims Fa12.6±2.1, Fe/Mn= 24.8±5.2, Cr2O3=0.5±0.1, CaO=0.3±0.0, n=13); pigeonite (Cores: Fs19.5±0.2Wo9.5±0.1, Fe/Mn=28.2±0.9, n=6; rims: Fs8.3Wo19.8, Fe/Mn=10.9, n=1). Classification: primitive achondrite (ureilite, U-S3, low weathering) Based on texture, mineral compositions, presence of graphite, sample is a ureilite. Specimens: Salek Mrabih (Dominions meteors) holds the main mass. A polished mount and an endcut weighing 21.5 g are on deposit at App. Data from: MB114 Table 0 Line 0: Origin or pseudonym: Bir Ounane DCA Date: 2024 Mass (g): 484 Pieces: 1 Class: Ureilite Shock stage: U-S3 Weathering grade: low Fayalite (mol%): 17.5±5.0 Ferrosilite (mol%): 17.9±4.2 Wollastonite (mol%): 11.0±3.9 Classifier: A. Love, App Type spec mass (g): 21.5 Type spec location: App Main mass: Salek Mrabih Finder: Hameti Mrabih Comments: Submitted by Anthony Love