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Allan Hills 84028 | |||||||||||||||||||||
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Basic information | Name: Allan Hills 84028 This is an OFFICIAL meteorite name. Abbreviation: ALH 84028 Observed fall: No Year found: 1984 Country: Antarctica [Collected by US Antarctic Search for Meteorites program (ANSMET)] Mass: ![]() | ||||||||||||||||||||
Classification history: |
This is 1 of 602 approved meteorites (plus 1 unapproved name) classified as CV3. [show all] Search for other: Carbonaceous chondrites, Carbonaceous chondrites (type 3), CV chondrites, and CV-CK clan chondrites | ||||||||||||||||||||
Writeup![]() |
Writeup from AMN 8(2):
Sample No:ALH84028 Location: Allan Hills Weight (g) 735.9 Field No.: 2850 Dimensions (cm): 9 x 8 x 6.5 Meteorite Type: C3V Chondrite
Macroscopic Description: Carol Schwarz Bubbly black fusion crust covers about 50% of this rounded specimen. Without fusion crust the sample is dark with lighter inclusions. Some salt deposit has formed. The interior is gray with numerous 1-2 mm lighter inclusions and a few oxidation haloes.
Thin Section (,4) Description: Glenn MacPherson This specimen shows no obvious evidence of terrestrial weathering. A variety of chondrules up to about 2 mm in diameter, clasts, and inclusions up to about 4 mm in maximum dimension are distributed throughout a pristine matrix consisting of (at least) abundant minute olivine plates of Fa45-50 composition, troilite, and awaruite. The chondrules are very well preserved, and many contain devitrified glass. The olivine in chondrules, and larger matrix grains, have a wide range of composition, from Fa0-30, but most are Fa0-10. Pyroxene grains having a composition close to Wo1 En97 Fs2 were found, although a wide range of compositions like that of olivine is presumably present. Fine-grained and coarse-grained refractory inclusions are present, including one large one (a Type A, irregular in shape) that contains gehlenitic melilite, spinel, and very titanium-rich fassaitic pyroxene. This is a beautiful example of a C3V carbonaceous chondrite. | ||||||||||||||||||||
Data from: MB76 Table 2 Line 993: |
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References: | Published in Antarctic Meteorite Newsletter 8(2) (1985), JSC, Houston Published in Meteoritical Bulletin, no. 76, Meteoritics 29, 100-143 (1994)
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Geography:![]() |
Statistics: This is 1 of 43700 approved meteorites from Antarctica (plus 3802 unapproved names) | ||||||||||||||||||||
Proximity search: |