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Graves Nunataks 06128
Basic information Name: Graves Nunataks 06128
     This is an OFFICIAL meteorite name.
Abbreviation: GRA 06128
Observed fall: No
Year found: 2006
Country: Antarctica [Collected by US Antarctic Search for Meteorites program (ANSMET)]
Mass:help 448 g
Antarctic Meteorite Newsletter:  AMN 30(2)  (2007)  Achondrite-ung
Meteoritical Bulletin:  MB 94  (2008)  Achon ungr
Recommended:  Achondrite-ung    [explanation]

This is 1 of 154 approved meteorites classified as Achondrite-ung.   [show all]
Search for other: Achondrites, Ungrouped achondrites
Comments: Approved 31 Aug 2007
Writeup from AMN 30(2):
Sample No.: GRA 06128; GRA 06129
Location: Graves Nunataks
Field No.: 17918; 17713
Dimensions (cm):   8.5 x 4.0 x 7.5;
8.0 x 5.0 x 2.5
Weight (g): 447.6; 196.450
Meteorite Type:

Achondrite Ungrouped

Macroscopic Description: Kathleen McBride
50% of the exteriors has shiny to glassy patches of black fusion crust. The exposed interior is rusty yellow in color and has fractures in a sort of plate-like orientation. The interior has small areas of gray crystalline material. It is a rusty to yellow-ocher color and very weathered.

Thin Section (,2) Description: Tim McCoy, Linda Welzenbach, Glenn MacPherson and Lauren LaCroix
The sections exhibit a granoblastic texture dominated by sodic plagioclase (>70 vol. % in the section studied) with lesser olivine and two pyroxenes, although mafic-rich pockets reaching several mm in size are present. Grain size is very heterogeneous; in one large feldspathic region the crystals are up to 5 mm, but elsewhere are rarely as large as 1 mm, perhaps suggesting formation as a breccia. Minor opaques include ilmenite (1.6% MgO), troilite, Fe,Ni-sulfide (pentlandite; 26% Ni), spinel (13% TiO2, 35% Cr2O3, 3% Al2O3), and Ni-Fe metal (67% Ni) that occurs only as minute inclusions inside of olivine. Silicates are equilibrated with olivine of Fa59, orthopyroxene of Fs44Wo2 (Fe/Mn~43), clinopyroxene of Fs19Wo43 (Fe/Mn~30-45) and oligoclase (An14Or2). The combination of its variable grain size, locally granoblastic texture, iron-rich mafics and sodium-rich plagioclase is unlike any known achondrite, including those of planetary origin.

Oxygen isotopic analysis: Z. Sharp, University of New Mexico
Oxygen isotopic analyses of three small (2-5 mg) pieces of GRA 06129 yielded the following results which fall in the Earth, Moon and enstatite meteorite field:

δ17O = 3.04, δ18O = 6.01, Δ17O = -0.09
δ17O = 2.89, δ18O = 5.63, Δ17O = -0.03
δ17O = 3.05, δ18O = 6.01, Δ17O = -0.07
[where Δ17O = δ17O - 0.52 x δ18O]


Thin Section Images

Plane-Polarized Light GRA06129 Cross Polarized Light
GRA06129 - Plane-Polarized Light GRA06129 - Cross Polarized Light

Lab Images

GRA 06128; GRA 06129
Data from:
  Table 4
  Line 4:
Mass (g):447.6
Class:Achon ungr
Weathering grade:CE
Plots: O isotopes:  
Search for this meteorite in the NASA/JSC database (U.S.):   
References: Published in Antarctic Meteorite Newsletter 30(2) (2007), JSC, Houston
Published in Meteoritical Bulletin, no. 94, MAPS 43, 1551-1588 (2008)
Find references in NASA ADS:
Find references in Google Scholar:
Photographs from AMN:
JSC A photo is in the write-up above


     This is 1 of 44547 approved meteorites from Antarctica (plus 3802 unapproved names)

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