20 grams. 30 x 25 x 20 mm. Eucrite-pmict
Fall not observed. Found 1987 in Antarctica.
Location Map of Antarctic Finds
AMN writes:
Macroscopic Description - Roberta Score
LEW87295 was found in the Lewis Cliff area emerging from the ice. The field team collected it by sawing a block of ice containing the meteorite. The ice block was sent to the Cold Regions Research and Engineering Lab in Hanover, New Hampshire, where the meteorite was removed. Care was taken to avoid contamination. The ice block remains in New Hampshire while the meteorite specimen resides in Houston.
Dull black fusion crust covers approximately 40% of this eucrite. Numerous vugs, typical of Antarctic eucrites, penetrate deep into the interior. Many clasts, polymineralic and monomineralic are present in the medium gray matrix. One notable clast is an easily extractable black clast whose dimensions are 6 x 5 x 4 mm. Some areas of rust are visible.
Thin Section Description (,4) - Brian Mason
The section shows clasts of pyroxene and plagioclase up to 1.8 mm long in a comminuted groundmass. Within the section there are individual brecciated clasts, up to 4 mm across. A black clast, 1.5 x 0.7 mm, appears to be a C2 carbonaceous chondrite; it contains chondrule-like aggregates of granular olivine and pyroxene up to 0.3 mm across. A patch of transparent brown glass, 0.6 mm long, is also present. Microprobe analyses show pyroxene compositions ranging fairly continuously from Wo2Fs59 to Wo42Fs24, the range in En content being quite limited; one clast of Mg-rich pyroxene, Wo3Fs20, was analyzed. Plagioclase composition is fairly uniform, averaging An91. One grain of a silica polymorph, probably tridymite, was noted. The brown glass is somewhat variable in composition, but averages (weight percent): SiO2 48, Al2O3 16, FeO 13, MgO 6.2, CaO 12, Na2O 3.6, K2O 0.2, MnO 0.5. The meteorite is a eucrite.
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