Our classified meteorites

in The Meteoritical Bulletin

On this page we share the basic information of the meteorites that we have officially classified.

All of them were originally samples recovered in the deserts and sent to the laboratory for analysis. Now they are exceptional pieces of collecting and research.

For more info about our lab, CLICK HERE.

 

Northwest Africa 10909

History: Six complete stones covered with dark fusion crust were found in the desert by a nomad. The stones (originally 201.3, 110.9, 121.7, 127.1, 100.3, and 152 g) were sent to MCM for study. After the first studies, several grams were sent to UPC, where analysis was performed by Dr. J. Llorca in October 2015.

Petrography: The meteorite displays a basaltic texture with up to 1.5 mm sized exsolved pyroxenes and equally sized lath-shaped calcic plagioclase. Minor phases include chromite, SiO2 polymorphs, ilmenite and metallic iron.

Geochemistry: Orthopyroxene; Fs57.4±0.9, Wo2.2±1.4, FeO/MnO = 32±1, n=19. Plagioclase; An87.1±2.6, n=21.

Classification: Monomict eucrite.

Northwest Africa 11397

History: In July 2015, Hamid Maatallaa, collaborator of MCM, recovered five pieces of the meteorite, which were sent to MCM for study. After the first observations, a sample for analysis was sent to Dr. Llorca, who carried out the classification.

Petrography: Breccia composed of disaggregated eucritic debris and some lithic eucrite clasts in a light matrix. Minerals include anorthite, pigeonite, augite, fayalite, silica polymorph, ilmenite, troilite and chromite. Minor Fe metal.

Geochemistry: Low-Ca pyroxene (Fs54.5±3.0Wo5.3±1.2, FeO/MnO=32-38, n=12), high-Ca pyroxene (Fs25.2±2.6Wo40.8±1.1, FeO/MnO=27-32, n=14); orthopyroxene host (Fs34.5±3.2Wo3.2±0.8, FeO/MnO=24-27, n=18), clinopyroxene exsolution lamella (Fs15.8±1.1Wo42.3±0.9, FeO/MnO=28-31, n=15), plagioclase (An90.3±3.3, n=22), fayalite (Fa92.2±2.0, FeO/MnO=41-42, n=11).

Classification: Eucrite, polymict.

Tocache

Geochemistry: Mineral compositions and geochemistry: Olivine (Fa20.1±0.8; N=82), low-Ca pyroxene (Fs16.6±0.6 Wo1.3±0.7; N=60), high-Ca pyroxene (Fs11.2 Wo25.7; N=1), feldspar (Ab78.3±4.5 An15.7±6.4 Or5.9±4.7; N=7). MEV/EDS: troilite (Fe = 64.7±0.6 wt%, S = 35.5±0.6 wt%; N=2), kamacite (Ni = 7.2±1.5 wt%; N=2), taenite (Ni = 29.8±3.7 wt%; N=2), tetrataenite (Ni = 46.2±0.6 wt%; N=1), chromite (Cr/(Cr+Al): 0.88±0.06; N=4), zoned Cr-spinel (edge = Cr/(Cr+Al): 0.58±0.05, Mg/(Mg+Fe): 0.22±0.03, Ti: 0.5±0.1 wt%; N=3) (center = Cr/(Cr+Al): 0.29±0.04, Mg/(Mg+Fe): 0.40±0.03; N=3), apatite (Cl: 5.0±0.2 wt%, F: 1.2±0.2 wt%; N=1), ilmenite and merrillite (RAMAN).

Classification: Ordinary Chondrite (H5), S3, W2.

Mederdra

Physical characteristics: Complete piece. It has primary fusion crust over 70% of the surface, secondary crust over 20%. The fusion crust is brown dark, thick, well preserved, and has contraction cracks. The rock measures 12 × 9.5 × 7.5 cm. It weighs 1552 g.

Petrography: Breccia containing chondrules and chondrule fragments embedded in a fine-grained yellow-brown matrix. Opaque phases are chromite and FeNi-sulfides. Metallic FeNi has not been found. Low-Ca pyroxene has not been found.

Geochemistry: Olivine, Fa39.2±0.8 (Fa38.1-42.2; n=20) Fe/Mn=82±1.5; pyroxene, Fs11.5±0.9Wo 45.0±1.1 (Fs10.2-12.7Wo43.7-46.6; n=15): Plagioclase: An9.7-11.1 (n=4).

Classification: R4-5, S2, W3

Northwest Africa 14005

Petrography: (Jose Garcia, MCM; D. Sheikh, Cascadia) This specimen is a breccia composed predominantly of sub-angular to sub-rounded anorthitic clasts (up to ~1.5 mm) and isolated mineral fragments of olivine and pyroxene set in a fine-grained matrix that contains interconnected areas of shock melt veins and trace amounts of ilmenite and troilite. Estimated modal abundances: Anorthitic plagioclase (90%), Olivine (3%), Pyroxene (3%), Shock melt veins (3%), Opaques (1%).

Geochemistry: (D. Sheikh, Cascadia) Olivine (Fa33.9±3.5, range Fa30.9-37.8, Fe/Mn=72±4, n=5), Low-Ca Pyroxene (Fs42.1±1.5Wo0.8±0.1, range Fs41.0-43.2Wo0.7-0.8, Fe/Mn=50±4, n=2), Pigeonite (Fs28.7±3.2Wo17.7±2.7, range Fs23.4-35.2Wo14.9-21.9, Fe/Mn=53±5, n=10), Augite (Fs21.0±4.0Wo32.0±4.6, range Fs16.9-24.8Wo27.9-37.0, Fe/Mn=53±6, n=3), Plagioclase (An96.0±0.5, range An94.8-97.0, n=36).

Classification: Lunar (feldspathic breccia).

Chwichiya 008

Petrography: Igneous rock with intersertal texture. Main minerals are pyroxene and plagioclase with typical grain size 400 µm. Other minerals include chromite, ilmenite, metal, troilite.

Geochemistry: Low-Ca pyroxene Fs59.3±0.6Wo2.7±0.4, FeO/MnO 30.2±2.0 (n=4). Augite exsolutions Fs26.6Wo43.3, FeO/MnO 30.3 (n=2). Plagioclase An89.2±0.3Ab10.5±0.4Or0.3±0.1 (n=4). Chromite Cr# 0.82.

Classification: Achondrite (eucrite)

Northwest Africa 14527

Physical characteristics: Black irregular rock with visible mm-sized white clasts. Cut surface show a black interior with white angular clasts to 5 mm.

Petrography: Mineral clasts to 400 µm set in a feldspathic glassy matrix containing vesicles with typical size 100 µm. Metal and troilite are present. One lithic clast, a 600 µm microgabbroic clast, was observed in the studied section.

Geochemistry: Olivine Fa24.8, FeO/MnO = 84.4 (n=2). Pyroxene Fs32.3±3.6Wo13.9±7.1, FeO/MnO = 59.1±7.5 (n=10). Plagioclase An94.0±2.6Ab5.8±2.5Or0.3±0.2 (n=6).

Classification: Lunar meteorite (Feldspathic breccia)

Northwest Africa 14801

Petrography: Brecciated gabbroic igneous rock with mm grain size. Main minerals are pyroxene and plagioclase. Accessory metal and troilite. Electron probe microanalyses reveal that pyroxene have diogenitic and eucritic compositions. The proportion of eucritic material is <10%.

Geochemistry: Diogenitic pyroxene Fs26.2±4.0Wo2.8±0.8, FeO/MnO=30.7±2.2 (n=7). Eucritic pyroxene Fs49.4Wo5.1, FeO/MnO = 30.5 (n=2). Plagioclase An94.5Ab5.1Or0.1 (n=1).

Classification: Achondrite (diogenite, polymict breccia).

Northwest Africa 14802

Physical characteristics: Grey stone. Cut surface reveals a gray interior with mm-sized darker clasts.

Petrography: Brecciated igneous rock with ophitic texture with typical grain size 250 µm. Main minerals are pyroxene (some exsolved, others zoned), and plagioclase. Accessory chromite, ilmenite, troilite, FeNi metal. A 2 × 2 mm melt rock clast is present.

Geochemistry: Pyroxene Fs35.1±5.7Wo3.3±2.1, FeO/MnO=36.8±4.8 (n=6). Plagioclase An86.0Ab13.4Or0.6 (n=2).

Classification: Achondrite (eucrite-br).

Northwest Africa 14803

Physical characteristics: Gray stone. Cut surface reveals a gray interior.

Petrography: Fractured but unbrecciated microgabbroic igneous rock with typical grain size 300 μm. Main minerals are exsolved pyroxene and plagioclase. Accessory troilite, ilmenite. No metal was observed.

Geochemistry: Pyroxene Fs60.4±1.0Wo1.9±0.2, FeO/MnO=36.0±3.5 (n=4). Plagioclase An81.6±1.3Ab17.2±0.7Or1.2±0.5 (n=3).

Classification: Achondrite (eucrite-unbr).

Northwest Africa 14816

Petrography:  Ordinary chondrite with a cluster texture [Metzler 2012, MAPS 47:2193-2217]. Opaque veins and melt rock clasts with microporphyritic texture are present.

Classification: Ordinary chondrite (L4).

Northwest Africa 15158

Petrography: Chondrite with large chondrules (average apparent diameter 1210±270, n=14), and cluster texture. Olivine is zoned. Opaque minerals are metal and troilite.

Geochemistry: Olivine Fa16.3±7.5, range Fa0.5-27.0, Fa PMD 36% (n=9). Cr2O3 in ferroan olivine 0.23±0.13 wt% (n=8). Low-Ca pyroxene Fs11.4±8.1Wo1.2±1.3, range Fs2.1-22.9 (n=10).

Classification: Ordinary chondrite (LL3).

Northwest Africa 15159

Physical characteristics: PENDING PUBLICATION.

Petrography: PENDING PUBLICATION.

Geochemistry: PENDING PUBLICATION.

Classification: Ordinary chondrite (L6).

Northwest Africa 15177

Petrography: Chondrite with mm-sized chondrule and CAIs to 2 mm set in an abundant fine-grained iron-rich matrix. Sulfides and magnetite are abundant. Metal, that includes awaruite, is rare.

Geochemistry: Olivine Fa4.0±2.8, range Fa1.6-8.7 (n=8). Low-Ca pyroxene Fs3.2Wo1.0 (n=2). Sulfides are troilite and pentlandite.

Classification: Carbonaceous chondrite (CV ox 3).

Smara 002

Physical characteristics: The meteorite is partially covered with fresh fusion crust. A cut surface reveals large chondrules and large CAIs set in a dark, fine grained matrix (about 75 vol.%).

Petrography: (V. Moggi Cecchi, MSN-FI; I.Abderrahmane, UMM; J.García, MCM; G.S.Senesi, CNR-ISTP): A polished section shows a chondritic texture with relatively large, well-formed PO and POP chondrules, ranging in size from 400 to 1500 μm, and set in a fine grained matrix (about 75 vol.%). CAIs consisting of melilite and spinel are present. Main silicate phases are Fo-rich olivine and Fs-rich orthopyroxene in chondrules and Fa-rich olivine in the matrix. Opaque phases mainly consist of framboidal magnetite inside chondrules and iron oxides as weathering products around chondrules. Pentlandite can be found as small blebs inside chondrules. Fe,Ni alloys are absent except for very rare awaruite grains.

Geochemistry: EMPA (V. Moggi Cecchi, MSN-FI): Ol in PO and POP chondrules (Fa4.7±3.9Fo95.3±3.5, N=45, Fe/Mn = 58.9;Cr2O3=0.2,CaO=0.3, all in Wt.%); Ol in matrix (Fa28.9±2.5Fo71.1±2.3, N=10); Opx in chondrules (Fs1.9±0.6En96.2±0.6Wo1.9±0.8, N=25, Fe/Mn = 18.3;Al2O3=1.2,Cr2O3=0.5, all in Wt.%); Magnetite with Cr2O3=1.5, Al2O3=0.6 (all in wt%).

Classification: Carbonaceous chondrite (CVox3).