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Calama 023 | |||||||||||||||||||||||||||||||||||||||
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Basic information | Name: Calama 023 This is an OFFICIAL meteorite name. Abbreviation: There is no official abbreviation for this meteorite. Observed fall: No Year found: 2017 Country: Chile Mass: ![]() | ||||||||||||||||||||||||||||||||||||||
Classification history: |
This is 1 of 6436 approved meteorites (plus 5 unapproved names) classified as H6. [show all] Search for other: H chondrites, H chondrites (type 4-7), Ordinary chondrites, and Ordinary chondrites (type 4-7) | ||||||||||||||||||||||||||||||||||||||
Comments: | Approved 14 Dec 2018 | ||||||||||||||||||||||||||||||||||||||
Writeup![]() |
Writeup from MB 107:
Calama 023 22°28.050’S, 68°38.786’W Antofagasta, Chile Find: 19 Oct 2017 Classification: Ordinary chondrite (H6) History: Meteorite (284.04 g) was found 19 October 2017 by the UrFU meteorite expedition-2017 in Chile (Pastukhovich A.Yu., Larionov M.Yu., Kruglikov N.A., Kolunin R.N.) near Chiu-Chiu, Calama region. Physical characteristics: Total mass is 284.04 g. The meteorite has roughly rounded shape. Exterior of the stone is desert polished. The surface and interior of the meteorite is light to dark brown in color due to Fe-hydroxides. No fusion crust was observed. Petrography: Classification (Victor V. Sharygin, SIGM and UrFU). Very rare chondrules in a coarse recrystallized matrix. Chondrules are poorly delineated and their sizes vary from 200 µm to 2 mm. The largest chondrules (1-2 mm) are visible macroscopically and represented by PO, POP and RP textural types. They mainly consist of olivine, low-Ca-pyroxene and plagioclase, diopside, and ±chromite and blebs of troilite and FeNi-metal. Olivine, low-Ca-pyroxene and plagioclase are main minerals in matrix. Clinopyroxene, chromite, ilmenite and merrillite (50-300 µm) occur locally in the matrix, chlorapatite was not observed. Large olivine grains from matrix and POP chondrules may contains partially crystallized (silicate-melt?) inclusions (low-Ca-pyroxene + diopside + plagioclase/glass + troilite). Plagioclase grains in the matrix are larger than 50 µm, indicating a petrologic type of 6 for the meteorite. The absence of opaque shock veins and weak undulatory extinction and irregular fractures in olivine indicate a shock stage of S2. Majority of grains of FeNi metal (kamacite, taenite, tetrataenite, up to 1.5 mm) and troilite (100-500 µm) are fresh. Pentlandite (±Ni-rich pyrrhotite, up to 50 µm) is rare in troilite on the contact with kamacite. In addition, alabandite + Ni-rich pyrrhotite (?) association (3x10 µm) was found in a kamacite-hosted troilite bleb (70 µm). Grains of copper (up to 5 µm) were observed in a kamacite-taenite-tetrataenite-troilite aggregate. Weathering products (goethite, Fe-Ni-Cl-hydroxide and other Fe-Ni-hydroxides, Fe-S-hydroxide) occur as in situ partial alteration of FeNi-metals and troilite and fill microfractures in minerals from matrix and chondrules (weathering grade – W2). The association of trevorite + akaganeite is common as an alteration product of Ni-rich metal grains (taenite or kamacite + taenite + tetrataenite). Rare Fe-Ni-hydroxides veins are crosscut the meteorite sample. Geochemistry: EDS-WDS analyses (Victor V. Sharygin, SIGM and UrFU). The primary chondrite paragenesis includes olivine Fa19.44±0.18 (N=36), orthopyroxene Fs17.28±0.35Wo1.45±0.14 (N=36), plagioclase Ab82.5An11.8Or5.7 (n=10), Cr-bearing clinopyroxene En47.4Fs7.0Wo45.6 (N=8, Cr2O3 – 0.83 wt.%), chromite Crt81.5Spl13.9 (N=16), ilmenite Ilm79.4Gk10.9 (N=10), merrillite, and FeNi-metals. Merrillite is poor in FeO (0.4-0.8 wt.%, N=14). Composition of metals and sulfides (in wt.%): kamacite (N=27) – Fe 92.83±0.31, Ni – 6.73±0.13, Co – 0.44±0.05; taenite (N=12) – Fe 75.44, Ni 24.26, Co 0.28; tetrataenite (N=14) – Fe 47.24, Ni 52.59, Co 0.14; pentlandite (N=5) – Fe 45.99, Ni 20.67, Co 0.27, S 33.05; alabandite (N=2) – Mn 53.45; Fe 9.12, Ni 1.09, Co 0.14, S – 36.28. Classification: Ordinary chondrite. H6, S2, W2. Specimens: 249.36 g sample – UrFU; 27.25 g sample and thin section – SIGM. | ||||||||||||||||||||||||||||||||||||||
Data from: MB107 Table 0 Line 0: |
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Institutions and collections |
UrFU: Ural Federal University, 620002, 19 Mira street, Ekaterinburg, Russia (institutional address; updated 14 Jan 2015) SIGM: V.S. Sobolev Institute of Geology and Mineralogy SB RAS, pr. Akademika Koptyuga, 3 Novosibirsk, 630090, Russia; Website (institutional address; updated 10 May 2017) |
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Catalogs: |
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References: | Published in Meteoritical Bulletin, no. 107, MAPS 55, 460-462
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Geography:![]() |
Statistics: This is 1 of 2340 approved meteorites from Antofagasta, Chile (plus 9 unapproved names) (plus 1 impact crater) This is 1 of 2369 approved meteorites from Chile (plus 15 unapproved names) (plus 1 impact crater) | ||||||||||||||||||||||||||||||||||||||
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