Northwest Africa 1195 Martian Shergottite |
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Northwest Africa 1195 Martian Shergottite |
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Assembled complete stone of shergottite NWA 1195 showing interior. The main mass on the left weighs 265 grams and the small end piece weighed 50 grams. The dark portion on the small endpiece is the 7.1 gram piece shown below. It was cut off to take to Morocco to see if it fit to the alleged find of the main mass. |
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This end-cut weighs 7.1 grams and measures 30.1mm by 20.3mm. The
thickness varies from 5.9mm to 2.3mm. This is the piece that Greg Hupe took to
Morocco with him to match up to the main mass that the Moroccans said that they had.
The story of this trip has been written by Greg and published in the August 2002
issue of Meteorite Magazine. The first photo shows the polished face of the specimen. The second photo shows the natural face of the endcut that fits perfectly to the main mass. The third photo shows the width of this piece. |
From the Meteoritical Bulletin #87 June, 2003:
A. and G. Hupe (Hupe) purchased a 50 g fragment of a broken stone with a distinctive, thin weathering rind collected by nomads near Safsaf, Morocco in 2002 March, and subsequently purchased the remainder of the same elongated stone (total weight 315 g). Dimensions of reassembled stone: 133 mm by 43mm by 37 mm. Classification and mineralogy (A. Irving and S. Kuehner, UWS): olivine megacrysts (up to 4 mm) are set in a groundmass of low-Ca pyroxene and maskelynite (Ab37Or0.5 to Ab41Or0.7) with minor Ti-chromite, pyrrhotite, ilmenite and Mg-bearing merrillite. The euhedral to subhedral shapes of most of the olivine grains suggest that they are phenocrysts rather than xenocrysts. Olivine exhibits strong compositional zoning (cores Fa19, FeO/MnO = 54; rims Fa40, FeO/MnO = 62), and contains abundant inclusions of chromite, clinopyroxene, orthopyroxene and pyrrhotite. The groundmass low-Ca pyroxenes are zoned from cores of pigeonite (Wo7Fs26, FeO/MnO = 37.1) or, less commonly, orthopyroxene (Wo4Fs23, FeO/MnO = 37.0) to rims of more Fe-rich pigeonite (Wo12Fs33, FeO/MnO = 36.6). Occurring very rarely on groundmass pyroxene grains are patchy overgrowths of an Fe-rich mineral (possibly related to chamosite or chlorite, with 35 wt.% FeO, 5 wt.% Al2O3, 1.5 wt.% MgO and a low oxide sum of 85 wt.%, suggesting the presence of water or hydroxyl). Calcite occurs sparsely along grain boundaries and as thin veinlets. Texture and mineral compositions are similar to those in olivine-phyric basaltic shergottite DaG 476/670, but olivine is much more magnesian than in other olivine-phyric basaltic shergottites SaU 005/008 and NWA 1068/1110. Specimens: type specimen, 20 g, and two polished thin sections, UWS; main mass, Hupe.
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