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Barnstable | |||||||||||||||||||||||||||||||||||||||
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Basic information | Name: Barnstable This is an OFFICIAL meteorite name. Abbreviation: There is no official abbreviation for this meteorite. Observed fall: No Year found: 2018 Country: United States Mass: ![]() | ||||||||||||||||||||||||||||||||||||||
Classification history: |
This is 1 of 6459 approved meteorites (plus 2 unapproved names) classified as H4. [show all] Search for other: H chondrites, H chondrites (type 4-7), Ordinary chondrites, and Ordinary chondrites (type 4-7) | ||||||||||||||||||||||||||||||||||||||
Comments: | Approved 23 Jan 2019 | ||||||||||||||||||||||||||||||||||||||
Writeup![]() |
Writeup from MB 108:
Barnstable 41.6969048°N, -70.3911813°W Massachusetts, United States Find: 2018 Aug 18 Classification: Ordinary chondrite (H4) History: The main mass was found on the surface resting in decomposing leaves surrounded with wild native blueberry bushes; other fragments were found similarly, covered with leaves with margins encased in soil, and some were found beneath the surface 1-4" deep. The first 1113 g fragment was found on August 18, 2018, and the main mass was discovered on September 11, 2018; remaining fragments were found between those date through 2018. All fragments were found in close proximity, in an area approximately 25’ × 5’, with smallest fragments toward one end. Physical characteristics: Specimen has a smooth surface with shallow regmaglypts. The main mass is 28 × 20.5 × 13 cm in size and appears oriented (shield orientation), with frothy roll over lip on one side. Some fragments have bits of remnant fusion crust, others show secondary fusion crust. White chondrules visible on most broken surfaces. Petrography: In addition to olivine and low-Ca pyroxene, there is minor Ca pyroxene (Fs6.9±0.7Wo44.2±0.7; n = 2) and plagioclcase (Ab83.1±0.7Or5.7±0.6; n = 6). Olivine and low-Ca pyroxene are homogeneous. Very few low-Ca pyroxene grains exhibit polysynthetic twinning. Chondrules are readily discernable and include the following textural types: BO, RP, PO, PP, POP, GOP. Only about 10-15% of the olivine grains show undulose extinction. There are no planar fractures. There are no coarse metal grains. All of the metallic Fe-Ni has been altered to limonite/goethite. There are a few feathered troilite grains remaining; also present are minor patches of clay minerals at the boundaries of mafic silicate grains. There is moderate silicate darkening in the specimen due to the presence of thin silicate-opaque veinlets. Also occurring are 30-40-µm-size chromite-plagioclase assemblages with 2-5-µm-size chromite grains. There are also small chromite veinlets containing plagiolcase patches within some olivine grains. The rock appears to have been shocked and annealed. | ||||||||||||||||||||||||||||||||||||||
Data from: MB108 Table 0 Line 0: |
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Institutions and collections |
UCLA: Institute of Geophysics and Planetary Physics, University of California, Los Angeles, CA 90095-1567, United States (institutional address; updated 17 Oct 2011) |
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Catalogs: |
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References: | Published in Meteoritical Bulletin, no. 108 (2020) Meteorit. Planet. Sci. 55, 1146-1150
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Photos: |
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Geography:![]() |
Statistics: This is 1 of 2 approved meteorites from Massachusetts, United States (plus 1 unapproved name) This is 1 of 1919 approved meteorites from United States (plus 867 unapproved names) (plus 28 impact craters) | ||||||||||||||||||||||||||||||||||||||
Proximity search: |