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| Northwest Africa 11405 | |||||||||||||||||||||||||||||||||
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| Basic information | Name: Northwest Africa 11405 This is an OFFICIAL meteorite name. Abbreviation: NWA 11405 Observed fall: No Year found: 2017 Country: (Northwest Africa) Mass:  54.5 g | ||||||||||||||||||||||||||||||||
| Classification history: |
This is 1 of 11 approved meteorites classified as R3-4. [show all] Search for other: Rumuruti chondrites, Rumuruti chondrites (type 3) | ||||||||||||||||||||||||||||||||
| Comments: | Approved 11 Sep 2017 | ||||||||||||||||||||||||||||||||
| Writeup |
Writeup from MB 106:
Northwest Africa 11405 (NWA 11405) (Northwest Africa) Purchased: 2017 Classification: Rumuruti chondrite (R3-4) History: One partially crusted stone weighing 54.5 g was found in Morocco prior to 2017. J. Donald Cline and John Sinclair acquired the sample from a meteorite dealer at the Tucson Gem and Mineral Show in February 2017. Physical characteristics: Sample is tabular in shape, dark brownish-green in color and contains one patch (~25% of surface) of weakly magnetic fusion crust that appears to be the bubbled trailing edge of an oriented stone. The interior is brownish-orange in color and has a clastic texture composed of chondritic clasts (some dark-colored) within a host of chondrules and fragments. No metal or sulfide is visible on the surface. Petrography: Description and classification (A. Love, App): Sample is a breccia composed of up to 15 mm clasts set within a host of well-defined chondrules (avg. dia. 353 μm) and fragments. Unequilibrated clasts contain chondrules with zoned olivine and pyroxene set within fine-grained matrix. Olivine chondrules display normal extinction and irregular fractures. Clinoenstatite is present. Within equilibrated clasts: olivines have uniform compositions; low and high Ca-pyroxenes are present; plagioclase occurs as isolated intergrowths and as networks similar to those found in type 4 and 5 R-chondrites. These components are hosted within a recrystallized matrix. Fine-grained FeS grains occur within some chondrules. Sulfides where present within matrix, are corroded and rare. Accessory minerals chromite. Geochemistry: (A. Love, App) Olivine (Host: Fa0.4-43.0, mean Fa23.7±13.7 CV=58%, N=21; Equilibrated clasts Fa38.5±0.1, N=6), Fe/Mn=75.6, NiO=0.1±0.2; Orthopyroxene (Host: Fs5.7-30.1Wo0.3-13.5, mean Fs17.9±8.2Wo2.6±3.1, N=16; Equilibrated clast Fs22.8Wo2.33, N=1); High-Ca pyropxene (Equilibrated clasts: Fs10.2±0.5Wo46.4±0.6, N=5). Classification: Rumuruti chondrite (R3-4, S1, W2). Based on Fa, Fe/Mn and Ni-bearing compositions of olivines, chondrule diameter and texture this sample is a Rumuruti chondrite. Based on the coefficient of variation of olivines within unequilibrated clasts, the petrologic subtype is estimated at 3.4. Specimens: PARI holds the main mass. One 11.04 g endcut and a polished thin section are on deposit at App. | ||||||||||||||||||||||||||||||||
| Data from: MB106 Table 0 Line 0: |
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| Institutions and collections |
App: Department of Geology, 572 Rivers St., Appalachian State University, Boone, NC 28608, United States (institutional address; updated 7 Mar 2013) PARI: Pisgah Astronomical Research Institute 1 Pari Dr Rosman, NC 28772, United States (institutional address; updated 13 Sep 2016) |
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| Catalogs: |
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| References: | Published in Gattacceca J., Bouvier A., Grossman J., Metzler K., and Uehara M. (2019) Meteoritical Bulletin, no. 106. Meteorit. Planet. Sci. 54 in press.
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| Geography: |
Statistics: This is 1 of 8495 approved meteorites from (Northwest Africa) (plus 1899 unapproved names) | ||||||||||||||||||||||||||||||||