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Northwest Africa 10414 | |||||||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 10414 This is an OFFICIAL meteorite name. Abbreviation: NWA 10414 Observed fall: No Year found: 2015 Country: (Northwest Africa) Mass: 39.8 g | ||||||||||||||||||||||||||||
Classification history: |
This is 1 of 329 approved meteorites (plus 2 unapproved names) classified as Martian (shergottite). [show all] Search for other: Martian meteorites | ||||||||||||||||||||||||||||
Comments: | Approved 23 Nov 2015 | ||||||||||||||||||||||||||||
Writeup |
Writeup from MB 104:
Northwest Africa 10414 (NWA 10414) (Northwest Africa) Purchased: 2015 Sept 1 Classification: Martian meteorite (Shergottite) Physical characteristics: Small complete stone with the shape of a shield. The crust is granular-looking. Petrography: (R. Hewins, S. Pont, B. Zanda, MNHNP) This meteorite consists of 77% weakly zoned pigeonite prisms, up to 4 × 1 mm in size, resembling a crystal mush. There is neither olivine nor augite present. The pigeonite is euhedral, highly fractured, with small feldspathic inclusions as well as ~200 nm exsolution lamellae. It is locally subophitic to plagioclase/maskelynite laths (~500 μm) on its margins. The interstices (22%) contain Si-rich mesostasis glass as well as plagioclase/maskelynite. The latter has euhedral Ca-rich cores visible in enhanced BSE, and zonation, though in normal contrast it appears to be unfractured maskelynite. Raman spectra of this transparent material are dominated by peaks of adjacent pyroxene and phosphate, but weak broad peaks near 500 and 600 cm-1 characteristic of maskelynite can be seen. Spinel (<1%) occurs mainly as inclusions in pigeonite. Accessory phases include ilmenite, merrillite, silica, baddeleyite and pyrrhotite, occurring on pigeonite margins or in interstitial feldspathic patches. There are small (~200 μm) patches of heterogeneous shock melt at some pigeonite-maskelynite contacts, with interfingering or veining of this melt and maskelynite. Adjacent "pigeonite" is lamellar to fibrous. Geochemistry: (R. Hewins, MNHNP) Pigeonite composition (mean, s.d.) is En54.3±6.7Fs36.2±5.5Wo9.5±2.2, with Fe/Mn (atomic) 35.0±7.1. Data fall on and below the Fe-Mn trend line for SNC, with some excluded high Mn points apparently related to alteration. Plagioclase/maskelynite is An46.4±4.1Ab51.1±3.6Or2.5±0.7, with a range of An54-36. The Cr-Ti spinel has up to 55 mol% chromite, up to 48% ulvöspinel and up to 35% magnetite. Classification: (R. Hewins, B. Zanda and S. Pont MNHN) The meteorite is classified as Martian (shergottite). It is a basaltic shergottite, but is unusual in being a pigeonite cumulate with no olivine or augite. Specimens: 8 g at MNHNP. The main mass is held by Labenne. | ||||||||||||||||||||||||||||
Data from: MB104 Table 0 Line 0: |
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Institutions and collections |
MNHNP: Museum National d'Histoire Naturelle, IMPMC-CP52, 57 rue Cuvier, 75005 Paris, France, France; Website (institutional address) Labenne: 23, rue de Esperance, 75013 Paris, France; Website (private address; updated 29 Aug 2012) MNHN: Museum National d'Histoire Naturelle, IMPMC-CP52, 57 rue Cuvier, 75005 Paris, France, France; Website (institutional address) |
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Catalogs: |
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References: | Published in Meteoritical Bulletin, no. 104, MAPS 52, 2284, Octover 2017, http://onlinelibrary.wiley.com/doi/10.1111/maps.12930/full
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Geography: |
Statistics: This is 1 of 9914 approved meteorites from (Northwest Africa) (plus 1841 unapproved names) |