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| Allan Hills A81021 | |||||||||||||||||||||||||
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| Basic information | Name: Allan Hills A81021 This is an OFFICIAL meteorite name. Abbreviation: ALHA81021 This meteorite may also be called Allan Hills 81021 (ALH 81021) in publications. Observed fall: No Year found: 1981 Country: Antarctica [Collected by US Antarctic Search for Meteorites program (ANSMET)] Mass:  695 g | ||||||||||||||||||||||||
| Classification history: |
This is 1 of 133 approved meteorites classified as EL6. [show all] Search for other: EL chondrites, Enstatite chondrites, Enstatite chondrites (type 4-7), and Enstatite-rich meteorites | ||||||||||||||||||||||||
| Writeup |
Writeup from AMN 6(1):
Sample No.: ALHA81021 Location: Allan Hills Field No.: 1424 Weight (gms): 695.1 Meteorite Type: E6 Chondrite
Physical Description: Carol Schwarz Flow lines mark the broad top surface of this otherwise smooth and flat specimen. The bottom surface has weathered more extensively than the top. The interior that was exposed is extremely weathered. Dimensions: 12 x 9 x 3 cm.
Petrographic Description: Brian Mason Only traces of chondritic structure are visible in the section, which consists largely of granular enstatite, with considerable nickel-iron (~20%), minor troilite and plagioclase, and accessory sinoite (Si2N2O, identified by its high birefringence). Weathering is extensive, with brown limonitic staining throughout the section. Remnants of fusion crust are present. Microprobe analyses show the enstatite is almost pure MgSiO3 (CaO 0.8%, FeO 0.2%, Al2O3 0.2%); plagioclase is An15Or4; the metal contains about 2% Si. The meteorite is an E6 chondrite. | ||||||||||||||||||||||||
| Data from: MB76 Table 2 Line 544: |
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| References: | Published in Antarctic Meteorite Newsletter 6(1) (1983), JSC, Houston Published in Meteoritical Bulletin, no. 76, Meteoritics 29, 100-143 (1994)
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Geography:
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Statistics: This is 1 of 44248 approved meteorites from Antarctica (plus 3802 unapproved names) | ||||||||||||||||||||||||
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