Name:Northwest Africa 482
Abbreviation:NWA 482
Country: (Northwest Africa)
(Northwest
Status:Valid
Fall: No
Year:2000
Class:Lunar (anorth)
TKW, g:1015
Bibliography:A 1015 g stone was purchased on 2001 January 10 in Alnif, Morocco, by Michael Farmer. The exact location of find is unknown but it is possibly in Algeria. The stone is complete, oriented, and appears relatively unweathered. Classification and mineralogy (A. Rubin and P. Warren, UCLA; D. Kring and I. Daubar, UAz): texture is typical of a crystalline impact melt breccia (polymict) with highland affinities; glassy and vesicular melt veins and melt pockets indicate shock subsequent to compaction by an impact event; plagioclase, An95.7Ab4.09Or0.17 (n = 136, UAz); olivine, Fo65–68 (average Fo66) with FeO/MnO = 88 ± 7 g/g (UCLA); olivine Fo68.4 with FeO/MnO = 93.9 ± 7.7 g/g (range: 78.7 to 111) (n = 51, UAz); pyroxene, Fs25Wo17 with nearly uniform Mg/(Mg + Fe) = 67–68 mol% and FeO/MnO = 51 ± 6 g/g (n = 10, UCLA); pyroxene, Wo10.3–51En32.6–63.9 Fs42.6–14.2, mean Mg/(Mg + Fe) = 68 mol%, FeO/MnO = 52 ± 8 g/g (n = 28, UAz); glassy melt veins occur in both UCLA and UAz samples; a 0.1 mm vein (UCLA) has SiO2 = 44.3 wt%, Na2O = 0.3 wt%, Al2O3 = 30.0 wt%, FeO = 3.6 wt%, MgO = 3.9 wt%, CaO = 17.3 wt%, and TiO2 = 0.3 wt%, which may approximate the bulk meteorite composition. Specimens: half of the main mass is with Farmer; 74 g, DPitt; type specimens, 24 g, UCLA, and 18 g, UAz.
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Photo courtesy: Jim Strope

Photo courtesy: Jim Strope

Photo courtesy: Jim Strope

Photo courtesy: Peter Marmet
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