Name: Graves Nunataks 95205 This is an OFFICIAL meteorite name. Abbreviation: GRA 95205 Observed fall: No Year found: 1995 Country: Antarctica [Collected by US Antarctic Search for Meteorites program (ANSMET)] Mass: 1460 g
Macroscopic Description: Kathleen McBride
The exterior of this achondrite has patches of dull black fusion
crust with polygonal fractures. Most of the fusion crust has
weathered away. The resulting surface is a rusty green-brown
color with numerous areas or patches of shiny melted-appearing
minerals. Several fractures are visible. This meteorite is very
hard and extremely difficult to break. The interior revealed white
to yellow minerals; pyroxene and plagioclase and oxides are present.
Some areas are completely rusty. Cleavage planes were visible
on some of the larger mineral grains. This achondrite has an
igneous texture.
Thin Section (,5) Description: Brian Mason
The section shows an aggregate of anhedral to subhedral grains,
up to 6 mm across, of olivine and pyroxene. Individual grains
are rimmed by carbonaceous material which contains trace amounts
of nickel-iron and troilite. The olivine crystals have been converted
into a mosaic of tiny grains, presumably by shock; the pyroxene
crystals appear to be unaffected, and show polysynthetic twinning.
Mineral compositions are slightly variable; mean values are olivine,
Fa21; pyroxene, Wo4Fs19. The
meteorite is a ureilite.