Sample Petrographic Description
| Sample Number | GRO 95534 |
| Newsletter | 19,2 |
| Location | Grosvenor Mountains |
| Field Number | 7618 |
| Dimensions (cm) | 3.0 x 2.7 x 1.5 |
| Weight (g) | 17.92 |
| Original Classification | Howardite |
| Pairing | GRO 95534; GRO 95535; GRO 95574; GRO 95581; |
| Mineral Composition (%Fa & %Fs) | |
| Ferrosilite (mol%): 20-53 | |
| Weathering | |
| A/B | |
| Fracturing | |
| A | |
| Macroscopic Description - Cecilia Satterwhite | |
| The exterior surfaces of these achondrite meteorites have smooth, shiny black fusion crust over seventy five percent of their surface. Areas where fusion crust has been plucked away reveal a gray matrix . The interior reveals a gray fine-grained texture with abundant white inclusions. A few green and black minerals are present. Minor oxidation is present. | |
| Thin Section Description (,3) - Brian Mason | |
| The sections are so similar that a single description will suffice; the meteorites are probably paired. They show a groundmass of comminuted pyroxene (orthopyroxene and pigeonite) and plagioclase (grains up to 0.2 mm), with a few larger mineral clasts and rare polymineralic clasts up to 2.5 mm across. Microprobe analyses show a wide range in pyroxene composition: Wo1-40, Fs20-60, En33-79, but with orthopyroxene clustered around Wo8Fs53 to Wo40Fs27 with fairly uniform En content. Plagioclase composition is An86-93. An SiO2 polymorph, probably tridymite, is present in accessory amounts. The meteorites are howardites. | |
| Notes | |
| GRO 95602 was initially paired with four other GRO howardites – GRO 95534, GRO 95535, GRO 95574, and GRO 95581. The relations between these five howardites have been re-evaluated by Mittlefehldt et al. (2013), Cartwright et al. (2014) and Lunning et al. (2016). Based on petrography, mineralogy, petrology, and bulk composition, GRO 95534, GRO 95535, GRO 95574, and GRO 95581 are paired together; GRO 95602 has been removed from this pairing group and is unpaired. AMN 45, no. 2. | |
| Antarctic Meteorite Images for Sample GRO 95534 | ||||
| Lab Photo(s) : | ||||
 |
 |
 |
 |
|
 |
 |
 |
||
| Antarctic Meteorite Images for Sample GRO 95534 | ||||
| Thin Section Photo(s) : | ||||
 |
 |
|||
| References for Sample GRO95534 | |
| Hahn, T. M., Lunning, N. G., McSween, H. Y., Bodnar, R. J., and Taylor, L. A., 2018, Mg-rich harzburgites from Vesta: Mantle residua or cumulates from planetary differentiation. Meteoritics & Planetary Science, 53, 514-546, doi: 10.111/maps.13036. | |
| Lunning, N. G., Welten, K. C., McSween, H. Y., Caffee, M. W., Beck, A. W., 2016, Grosvenor Mountains 95 howardite pairing group: Insights into the surface regolith of asteroid 4 Vesta. Meteoritics & Planetary Science, 51(1), 167-194. | |
| Lunning, N. G., Mcsween Jr., H. Y., Tenner, T. J., Kita, N. T., Bodnar, R. J., 2015, Olivine and pyroxene from the mantle of asteroid 4 Vesta. Earth and Planetary Science Letters, 418, 15-May-15, 126-135, ISSN 0012-821X, http://dx.doi.org/10.1016/j.epsl.2015.02.043. | |