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Northwest Africa 5784 | |||||||||||||||||||||||
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Basic information | Name: Northwest Africa 5784 This is an OFFICIAL meteorite name. Abbreviation: NWA 5784 Observed fall: No Year found: 2008 Country: Morocco Mass: ![]() | ||||||||||||||||||||||
Classification history: |
This is 1 of 518 approved meteorites classified as Diogenite. [show all] Search for other: Achondrites, Diogenites, and HED achondrites | ||||||||||||||||||||||
Comments: | Approved 14 May 2010 | ||||||||||||||||||||||
Writeup![]() |
Writeup from MB online:
Northwest Africa 5784 (NWA 5784) Morocco Purchased: 2008 Classification: HED achondrite (Diogenite) History: A single 2.6 kg, dark brown stone was purchased in February 2008 from a Moroccan dealer at the Tucson Gem and Mineral Show by Blaine Reed. Petrography: A cataclastic dunite that contains (in vol. %) olivine, 91; plagioclase, 5; low-Ca pyroxene, 2; chromite and Fe-metal, 2. Severe crushing is prevalent throughout the rock; many of the olivine and plagioclase fragments show mottled extinction. Finest grain size domains are recrystallized. Slight staining around tiny metal grains was observed. Geochemistry: Olivine (Fa31.3; FeO/MnO = 34); plagioclase (An94.5); chromite (cr# = 70); metal (Ni = 0.35 wt %). Oxygen isotopes (D. Rumble, CIW): Replicate analyses of acid-washed whole rock samples by laser fluorination gave, respectively, δ18O = 3.56, 3.10; δ17O = 1.67, 1.39; Δ17O = -0.205, -0.243 per mil. Classification: Achondrite (diogenite). Mineral compositions and oxygen isotopic composition suggest affinity with diogenites. The meteorite is olivine-rich compared to diogenites and may be considered a dunitic (or olivine-rich) diogenite. Specimens: A total of 20.6 g is on deposit in the PSF collection at FMNH. Reed holds the main mass. | ||||||||||||||||||||||
Data from: MB98 Table 1 Line 35: |
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Plots: | O isotopes: | ||||||||||||||||||||||
Institutions and collections |
FMNH: Department of Geology
The Field Museum of Natural History
1400 South Lake Shore Drive
Chicago, IL 60605-2496, USA, United States; Website (institutional address; updated 16 Nov 2011) NAU: Geology, Bldg 12 Knoles Dr Northern Arizona University, Flagstaff, AZ 86011, United States; Website (institutional address; updated 12 Apr 2012) PSF: Planetary Studies Foundation,10 Winterwood Lane, Unit B, Galena, Illinois 61036-9283, United States; Website (institutional address; updated 1 Dec 2011) CIW: Carnegie Insitution Washington, Geophysical Laboratory, 5251 Broad Branch Rd., NW, Washington DC 20015, United States (institutional address) Reed: Blaine Reed, P.O. Box 1141, Delta, CO 81416, United States; Website (private address) |
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Catalogs: |
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References: | Published in Meteoritical Bulletin, no. 98, MAPS 45, 1530-1551 (2010)
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Geography:![]() |
Statistics: This is 1 of 2012 approved meteorites from Morocco (plus 35 unapproved names) (plus 1 impact crater) |