Sample Petrographic Description
Sample Number | GRA 98168 |
Newsletter | 23,1 |
Location | Graves Nunataks |
Field Number | 11904 |
Dimensions (cm) | 2.5 x 1.0 x 1.5 |
Weight (g) | 7.01 |
Original Classification | Howardite |
Mineral Composition (%Fa & %Fs) | |
Ferrosilite (mol%): 26 | |
Weathering | |
A | |
Fracturing | |
A | |
Macroscopic Description - Kathleen McBride | |
The exterior has dull brown/black fusion crust over 50% of its surface. The interior is a light gray matrix with some minor rust and millimeter sized tan inclusions. | |
Thin Section Description (,2) - Tim McCoy | |
The section shows a groundmass of comminuted pyroxene and plagioclase (up to 0.5 mm) with coarse-grained clasts up to a few mm. The section is dominated by orthopyroxene of relatively constant composition (Fs24-31Wo2-7). A few grains of feldspar were analyzed (An89-94Wo0.3). Some of the pyroxene grains seem to exhibit submicron exsolution and this may explain the range in pyroxene compositions. The meteorite is probably a howardite, but contains relatively little eucritic material. It is probably not paired with GRA98030. |
Antarctic Meteorite Images for Sample GRA 98168 | ||||
Thin Section Photo(s) : | ||||