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Northwest Africa 4741 | |||||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 4741 This is an OFFICIAL meteorite name. Abbreviation: NWA 4741 Observed fall: No Year found: 2005 Country: (Northwest Africa) Mass: ![]() | ||||||||||||||||||||||||||
Classification history: |
This is 1 of 131 approved meteorites classified as Achondrite-ung. [show all] Search for other: Achondrites, Ungrouped achondrites | ||||||||||||||||||||||||||
Comments: | Approved 26 Oct 2010 | ||||||||||||||||||||||||||
Writeup![]() |
Writeup from MB 99:
Northwest Africa 4741 (NWA 4741) (Northwest Africa) Found: unknown Classification: Ungrouped achondrite History: One single stone purchased in Erfoud, June 2005. Physical characteristics: The stone measures 40×20×15 mm and weighs 20 g. It is 70% covered with dark brown fusion crust and discrete regmaglypts. The interior is light gray and fine grained. Petrography: (A. Jambon, O. Boudouma, D. Badia, UPVI; J-A Barrat and M. Bohn, UBO). Dominant olivine and low-Ca pyroxene exhibit thin, iron-enriched rims at the contact with interstitial glass. Troilite, chromite, kamacite, taenite, and augite are also present. The sample is partly brecciated and shock melted. Some crystals of olivine and pyroxene have serrated overgrowths a few micrometers wide. Mode (vol %): olivine = 24%; pyroxene = 64%; glass = 6 %; voids 4%; accessories 2%. Geochemistry: Olivine: Fo97, FeO/MnO = 20. Enstatite: En94Fs5Wo1, FeO/MnO = 19. Major elements by ICP-AES and trace element composition by ICP-MS (J.-A. Barrat UBO): silicic-feldspathic glass: SiO2 = 76-68 wt%; Al2O3 = 6-13 wt%; FeO = 4-7 wt%; CaO = 2-10 wt%; Na2O = 1-4 wt%; K2O = 0.7-0.2 wt%. Bulk composition: SiO2 =52.7 wt%; MgO = 37.3 wt%; FeO = 6.06 wt%; NiO = 0.1 wt%. Incompatible elements abundances close to chondritic. Light REE depleted pattern with La/Lu = 0.57 × chondritic. Negative Eu anomaly, Eu*/Eu = 0.60. Anomalous ratio of Na/K = 3.0 (by wt). Oxygen Isotopes (R. Greenwood and I. Franchi, OU): δ18O = 4.99 ‰, δ17O = 2.64 ‰, Δ17O = 0.047 ‰. Classification: Achondrite (ungrouped). Only marginally weathered. Shock melted. Specimens: A total sample mass of 5 g and one polished section are on deposit at UPVI. An anonymous collector holds the main mass. | ||||||||||||||||||||||||||
Data from: MB99 Table 0 Line 0: |
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Plots: | O isotopes: | ||||||||||||||||||||||||||
Institutions and collections |
OU: Planetary and Space Sciences
Department of Physical Sciences
The Open University
Walton Hall
Milton Keynes
MK7 6AA
United Kingdom, United Kingdom (institutional address; updated 8 Dec 2011) UPVI: Université Pierre et Marie Curie (Paris VI),Case 110, 4 Place Jussieu, 75005 Paris, France (institutional address; updated 5 Oct 2014) UBO: Institut Universitaire Européen de la Mer, Université de Bretagne Occidentale, place Nicolas Copernic, F-29280 Plouzané Cedex, France (institutional address; updated 15 Sep 2017) |
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Catalogs: |
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References: | Published in Meteoritical Bulletin, No. 99, April 2012, MAPS 47, E1-E52 (2012) [published online only]
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Geography: |
Statistics: This is 1 of 9116 approved meteorites from (Northwest Africa) (plus 1873 unapproved names) |