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Northwest Africa 13170 | |||||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 13170 This is an OFFICIAL meteorite name. Abbreviation: NWA 13170 Observed fall: No Year found: 2015 Country: (Northwest Africa) Mass: ![]() | ||||||||||||||||||||||||||
Classification history: |
This is 1 of 140 approved meteorites classified as Achondrite-ung. [show all] Search for other: Achondrites, Ungrouped achondrites | ||||||||||||||||||||||||||
Comments: | Approved 17 Feb 2020 | ||||||||||||||||||||||||||
Writeup![]() |
Writeup from MB 109:
Northwest Africa 13170 (NWA 13170) (Northwest Africa) Purchased: May 2015 Classification: Ungrouped achondrite History: Bought in Erfoud, Morocco, in May 2015. Physical characteristics: A dark-brown stone. Cut surface reveals a homogeneous dark interior. Petrography: (J. Gattacceca, CEREGE) Equilibrated equigranular texture with triple junctions. Main mineral are olivine and pyroxene (grain size 200 μm), plagioclase (grain size 100 μm, 17 vol%), FeS (8 vol%, well preserved, grain size 100 μm). Accessory metal (mostly replaced by weathering products), chromite. No chondrule visible in the 1 cm2 section. Geochemistry: Olivine Fa30.8±0.3, CaO 0.08±0.01 wt%, FeO/MnO=81.4±8.9 (N=7). Ca-pyroxene Fs10.4±0.8Wo44.3±1.4 (N=5). No low-Ca pyroxene was found in the section. Plagioclase An30.4±0.8Ab66.7±0.8Or2.9±0.1 (N=4). Chromite Cr/(Cr+Al) = 0.76 (N=1). Oxygen isotopic composition (J. Gattacceca, C. Sonzogni, CEREGE) from analysis of one acid-washed 1.5 mg aliquot of a powdered 185 mg bulk sample is δ17O=-2.28‰, δ18O=0.97‰, Δ17O=-2.79‰ (linearized, slope 0.5247, analytical uncertainties 0.08‰, 0.12‰, 0.03‰ respectively). Magnetic susceptibility log χ (× 10-9 m3/kg) = 3.68. Classification: Achondrite-ungrouped. The oxygen isotopic composition is far removed from other achondrite groups. The mineralogy and mineral composition are similar to NWA 10503, but oxygen isotopic composition is different. Specimens: 15 g and a polished section at CEREGE. Main mass with Luc Labenne. | ||||||||||||||||||||||||||
Data from: MB109 Table 0 Line 0: |
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Plots: | O isotopes: | ||||||||||||||||||||||||||
Institutions and collections |
CEREGE: CEREGE
BP 80
Avenue Philibert, Technopole de l'Arbois
13545 Aix-en-Provence Cedex 4
France, France (institutional address; updated 10 Jun 2023) Labenne: 23, rue de Esperance, 75013 Paris, France; Website (private address; updated 29 Aug 2012) |
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Catalogs: |
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References: | Published in Meteoritical Bulletin, no. 109, in preparation (2020)
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Geography: |
Statistics: This is 1 of 9429 approved meteorites from (Northwest Africa) (plus 1876 unapproved names) |