| MetSoc Home Publications Contacts |
|
||
|
||
| Northwest Africa 15256 | |||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Basic information | Name: Northwest Africa 15256 This is an OFFICIAL meteorite name. Abbreviation: NWA 15256 Observed fall: No Year found: 2000 Country: Morocco Mass:  5.65 kg | ||||||||||||||||||||||||||||||||
| Classification history: |
This is 1 of 695 approved meteorites (plus 2 unapproved names) classified as H3. [show all] Search for other: H chondrites, H chondrites (type 3), Ordinary chondrites, and Ordinary chondrites (type 3) | ||||||||||||||||||||||||||||||||
| Comments: | Approved 14 Sep 2022 | ||||||||||||||||||||||||||||||||
| Writeup |
Writeup from MB 111:
Northwest Africa 15256 (NWA 15256) Morocco Purchased: 2000 Classification: Ordinary chondrite (H3) History: Sample was purchased in 2000 at the Tucson mineral show from A. Aaronson who acquired it from Morocco. Sample is catalogued at ROM as M60299. Physical characteristics: Bears regmalypted surface. Fusion crust is complete, showing some dun brown weathering and a moderate desert polish. Stone has some throughgoing cracks. Petrography: In polished thin section, chondrules of types POP, CC, RP and PO are well-delineated in a dark matrix. Chondrules have diameters 548±216 µm (n=41). Olivine and pyroxene grains have sharp to undulatory extinction. Metal grains are rare and surrounded by or entirely replaced by Fe oxides. Fe oxides pervasively line void walls and fill cracks throught section. In BSE images, Ca-poor pyroxene shows zoning to Fe rich rims and some mesostasis appears to consist of compositionally varying feldspathic glass. Geochemistry: EPMA: Olivine: Fa16.46±4.84 (n=32); Ca-poor pyroxene: Fs11.45±6.44Wo1.09±0.75 (n=25); Ca-rich pyroxene: Fs7.31±5.42Wo38.74±6.68 (n=5). Magnetic susceptibility measured on a 2.81 g less weathered slice is log χ (× 10-9 m3/kg) = 4.71. A vuggy, fractured and highly weathered 16.84 g slice has log χ (× 10-9 m3/kg) = 4.57. Classification: Ordinary chondrite: H3 (S2) W4. Chondrule size, definition, EPMA olivine and pyroxene compositions and compositional variation are most consistent with H3 chondrite. Bulk magnetic susceptibility is consistent with a strongly weathered H chondrite. Specimens: Type specimen location: ROM. Main mass: DGregory. | ||||||||||||||||||||||||||||||||
| Data from: MB111 Table 0 Line 0: |
|
||||||||||||||||||||||||||||||||
| Institutions and collections |
ROM: Royal Ontario Museum, 100 Queen's Park, Toronto, Ontario M5S 2C6, Canada (institutional address; updated 18 Oct 2011) UWO: University of Western Ontario, Department of Earth Sciences, BGS 1026, 1151 Richmond St. N, London, Ontario, Canada N6A 5B7, Canada (institutional address; updated 18 Jul 2015) Aaronson: Sahara Overland Ltd., Harhora, Temara, 12000, Morocco (private address; updated 3 Jan 2010) DGregory: David Gregory, 230 First Avenue, Suite 108, St. Thomas, Ontario N5R 4P5, Canada (private address) |
||||||||||||||||||||||||||||||||
| Catalogs: |
| ||||||||||||||||||||||||||||||||
| References: | Published in Meteoritical Bulletin, no. 111, in preparation (2022)
| ||||||||||||||||||||||||||||||||
Geography:
|
Statistics: This is 1 of 2003 approved meteorites from Morocco (plus 31 unapproved names) (plus 1 impact crater) | ||||||||||||||||||||||||||||||||