THE METEORITICAL BULLETIN 84-1 June 2, 2000 Jeffrey N. Grossman, Editor (email@example.com) Meteoritical Bulletin, No. 84, 2000 August Dar al Gani 670 exact location unknown Libya Found 1999 Martian basalt (shergottite) A dark-brown stone, broken into three adjoining pieces, with a total mass of 1619 g, was found in the Dar al Gani region. Mineralogy and classification (L. Folco, MNA-SI): cm-sized patches of fusion crust are present on the external surfaces; porphyritic texture consisting of mm-sized phenocrysts of brown olivine (Fo58-80) set in a fine grained basaltic groundmass of tabular pyroxene and interstitial feldspathic glass (An52-72Or0-1); pyroxene is primarily pigeonite (En56-66Wo9-13) with subordinate enstatite (En73-82Wo2-3) and augite (En48-50Wo31-36); other minerals are chromite, titanian chromite, ilmenite, merrillite and pyrrhotite; shock features include strong mosaicism and planar deformation in olivine, undulose extinction and twinning in pyroxene, and abundant impact melt pockets and veinlets; pervasive veins filled in by calcite are due to terrestrial weathering. Oxygen isotopes (A. Sexton and I. A. Franchi, OU): d17O = +2.83 \211, d18O = +4.95 \211, D17O = +0.26 \211. The petrography and level of terrestrial weathering are essentially identical to those of DaG 476 and DaG 489, and the three are very likely paired. Specimens: main mass with anonymous finder; 11.9 g and one polished thin section at MNA-SI.
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