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Northwest Africa 10929 | |||||||||||||||||||||||||||
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Basic information | Name: Northwest Africa 10929 This is an OFFICIAL meteorite name. Abbreviation: NWA 10929 Observed fall: No Year found: 2015 Country: (Northwest Africa) Mass: ![]() | ||||||||||||||||||||||||||
Classification history: |
This is 1 of 498 approved meteorites classified as Diogenite. [show all] Search for other: Achondrites, Diogenites, and HED achondrites | ||||||||||||||||||||||||||
Comments: | Approved 3 Dec 2016 | ||||||||||||||||||||||||||
Writeup![]() |
Writeup from MB 105:
Northwest Africa 10929 (NWA 10929) (Northwest Africa) Purchased: 2015 Classification: HED achondrite (Diogenite) History: On 2015, meteorite specimens were purchased by José Antonio Sanchez Santana in the Saharawi refugee camps in Tindouf, Algeria. Physical characteristics: Three stone fragments (34, 23 and 3 g) with black fusion crust covering 10% of the stones. A saw cut and broken surface reveals numerous mm-sized green crystals set in light-yellow groundmass. Petrography: Petrographic description (J. Llorca, UPC). The meteorite is a orthopyroxene-rich breccia dominated by <1 to 4 mm grains set in a fine-grained cataclastic orthopyroxene matrix. The section contains about 99 vol.% orthopyroxene with accessory kamacite (50-400 ?m), troilite (30-50 ?m), Al-rich chromite (10-50 ?m) and Ca-rich pyroxene (50-100 ?m). Most accessory minerals surround large orthopyroxene grains. The section is notable for the absence of olivine and plagioclase. Geochemistry: Mineral compositions (R.P. Lozano, IGME). Large grains and matrix unzoned orthopyroxene have the same compositions. Microprobe analyses show orthopyroxene ranges from Fs25-30Wo1-2 with a mean of Fs26.4±1.2Wo1.7±0.2 and Fe/Mn=35-47 (mean Fe/Mn=40.3±3.7) (n=17). Ca-rich pyroxene ranges are Fs9-11Wo44-46 (means: Fs9.4±1.0Wo44.5±0.8) and Fe/Mn=24-75 (mean: Fe/Mn=39.5±19.4) (n=6). The metal is kamacite whit Ni=1.3-1.5 and Co=1.1-1.2 (all in wt.%; n=16). Chromite has mean Cr/(Cr+Al)=0.93 (n=3). Bulk chemistry (J. Reyes, IGME). 0.5 grams of sample for analysis. XRF of subsample gave abundances of (in wt.%): SiO2=53.56, TiO2<0.10, Al2O3=0.52, Fe2O3=17.04, MgO=26.09, CaO=1.16 and K2O<0.10. Na2O= 0.05 wt.% by AAS. Trace elements were measured with ICP-MS (all in ppm): Be<0.1, V=85.3, Cr=2960, Co=10.7, Ni=13.9, Cu<0.5, Zn<2, As=0.14, Se<1, Mo<0.5, Ag<0.1, Cd=3.2, Sb=0.15, Ba=12.3, Tl<0.1, Pb<2, Th<0.1 and U<0.1. Classification (R. P. Lozano, IGME). Achondrite, diogenite. Terrestrial weathering is not significant. Specimens: Type specimen (11 g), two co-type specimens (1.0 + 2.1 g) and a probe mount are on deposit at Museo Geominero (IGME). A thin section is on deposit at UPC. José Antonio Sánchez Santana holds the main mass. | ||||||||||||||||||||||||||
Data from: MB105 Table 0 Line 0: |
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Institutions and collections |
UPC: Institut de Tècniques Energètiques, Universitat Politècnica de Catalunya
Diagonal 647, ed. ETSEIB, 08028 Barcelona, Spain, Spain (institutional address; updated 3 May 2015) IGME: Museo Geominero, Instituto Geológico y Minero de España, Ríos Rosas 23, 28003 Madrid, Spain (institutional address; updated 12 Dec 2012) |
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Catalogs: |
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References: | Published in Meteoritical Bulletin, no. 105, MAPS 52, 2411, September 2017. http://onlinelibrary.wiley.com/doi/10.1111/maps.12944/full
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Geography: |
Statistics: This is 1 of 8495 approved meteorites from (Northwest Africa) (plus 1899 unapproved names) |