Shergottites
Name
*click on the Name for more information
Structure Class
achondrites
Chemical Class
Martian (shergottite)
Country
Year found
2018
Mass
1150 g
[Museum Collection]
(1) 0.51g
History: Purportedly found in Algeria and purchased by Mohamed Brahim Sueilem in August 2018 from a dealer in Bordj Badji Mokhtar, Algeria. Physical characteristics: The material (total weight 1150 g) comprises multiple broken fragments, some with adhering black fusion crust. The friable pieces are pale green in color and contain white plagioclase but no evident maskelynite. Petrography: (A. Irving and S. Kuehner, UWS) This fresh specimen has an orthocumulate texture with ~15 vol.% lath-like, birefringent plagioclase occurring interstitially to more abundant and coarser grained (0.2-1.6 mm, mean 0.7 mm) mafic silicate grains (unzoned olivine and patchily zoned low-Ca and high-Ca clinopyroxene with very limited compositional variation). Accessory phases include Mg-merrillite, chlorapatite, ilmenite, Ti-rich chromite, Cr-rich chromite and pyrrhotite (some associated with minor pentlandite). Levels of shock are judged to be low, based on the absence of optical effects in plagioclase and the complete lack of any conversion to maskelynite; the presence of widespread microcracks in mafic silicates is the only clear evidence of shock. Geochemistry: Olivine (Fa32.7-34.3, FeO/MnO = 47-48, N = 4), pigeonite (Fs25.0-30.4Wo5.5-10.0, FeO/MnO = 28-30, N = 4), subcalcic augite (Fs17.1-18.1Wo32.7-32.4, FeO/MnO = 23-25, N = 2), aluminous augite inclusion in olivine (Fs17.1Wo39.5, FeO/MnO = 28, TiO2 = 1.1 wt.%, Al2O3 = 6.2 wt.%), plagioclase (An43.0-57.8Or2.4-1.3, N = 3). Oxygen isotopes (K. Ziegler, UNM): analyses of acid-washed subsamples by laser fluorination gave, respectively, δ17O 2.907, 2.635, 2.808; δ18O 5.092, 4.620, 4.875; Δ17O 0.218, 0.195, 0.234 per mil. Classification: Martian (shergottite, olivine gabbroic, orthocumulate, low shock). Specimens: 22.4 g including one polished thin section at UWB; remainder held jointly by Naji Ben Faraji and Mohamed Brahim Sueilem.
Name
*click on the Name for more information
Structure Class
achondrites
Chemical Class
Martian (shergottite)
Country
Year found
2018
Mass
3.29 kg
[Museum Collection]
(1) 2.79g (2) 1.26g
History: Purchased in Ouarzazate, Morocco by Mohamed Aid in July 2018. Petrography: (A. Irving and S. Kuehner, UWS; P. Carpenter, WUSL) Medium-grained with diabasic texture and some small, dark glassy shock melt pockets. Composed predominantly of zoned clinopyroxene and maskelynite with accessory fine grained intergrowths of hedenbergite+fayalite+silica, Fe-Ti oxide (finely exsolved), merrillite and pyrrhotite. Geochemistry: Subcalcic augite (Fs28.5-30.6Wo28.2-23.7, FeO/MnO = 30, N = 2), pigeonite (Fs41.3Wo15.5, FeO/MnO = 31), ferropigeonite (Fs71.1-83.4Wo17.1-11.3, FeO/MnO = 38-45, N = 4), maskelynite (An50.9-52.1Or2.1, N = 2). Classification: Martian (shergottite, diabasic) Specimens: 26.3 g including one polished thin section at UWB; remainder with Aaronson.
Name
*click on the Name for more information
Structure Class
achondrites
Chemical Class
Martian (shergottite)
Country
Year found
2018
Mass
1679 g
[Museum Collection]
(1) 7.02g (2) 1.34g
History: Purchased in Ouarzazate, Morocco by Mohamed Aid in July 2018. Petrography: (A. Irving and S. Kuehner, UWS; P. Carpenter, WUSL) Relatively fine grained with intersertal texture. Composed predominantly of zoned clinopyroxene and maskelynite (some exhibiting a curved, narrow lath-like habit) with accessory fine grained intergrowths of hedenbergite+fayalite+silica, Fe-Ti oxides, merrillite and pyrrhotite. Geochemistry: Subcalcic augite (Fs24.8-41.8Wo31.4-24.3, FeO/MnO = 30-33, N = 3), ferropigeonite (Fs66.9-73.0Wo16.6-16.5, FeO/MnO = 41-43, N = 2), maskelynite (An51.9-53.1Or1.3-1.2, N = 2). Classification: Martian (shergottite, fine-intersertal) Specimens: 20.5 g including one polished thin section at UWB; remainder with Mr. Aaronson.
Name
*click on the Name for more information
Structure Class
achondrites
Chemical Class
Martian (shergottite)
Country
Year found
2018
Mass
150 g
[Museum Collection]
(1) 9.59g (2) 0.97g (3) 0.82g
History: Found in Algeria in 2018 and purchased from a Moroccan dealer by Huapei Wang in 2018 Physical characteristics: These stones are (partially) covered by black fusion crust and appear to be very fresh and unaltered. Numerous vesicles are seen in the fusion crust. The interior is composed of yellow green grains with interstitial pale gray grains. Petrography: The rock has a medium-grained subophitic texture. It consists of elongated prismatic pyroxene (up to 1.5 mm in length) and lath-like plagioclase (up to 1.8 mm in length), with accessory titanomagnetite, ilmenite, silica polymorph, merrillite, pyrrhotite, fayalite. Pyroxenes show patchy zoning from Mg-rich core to Mg-poor rim, with irregular boundaries. Ilmenite occurs as thin lamellae intergrown with titanomagnetite. Geochemistry: Pyroxenes are zoned from augite cores (En45.3Wo25.6, FeO/MnO = 28.5) and pigeonite cores (En40.3Wo19.6 FeO/MnO = 32.3) to ferropigeonite rims (En8.4Wo14.5 FeO/MnO = 41.1). Plagioclase is characterized by homogeneous compositions of An52 Or1.4. Titanomagnetite (TiO2 29.4 wt%, FeO 65.5 wt%, Al2O3 1.3 wt%); ilmenite (TiO2 48.9 wt%, FeO 49.8 wt%).
Name
*click on the Name for more information
Structure Class
achondrites
Chemical Class
Martian (shergottite)
Country
Year found
2019
Mass
49 g
[Museum Collection]
(1) 4.3g
History: Purchased in 2019 by Miguel Angel Contreras Gomez from a meteorite dealer in Algeria. Physical characteristics: This sample has a weathered fusion crust exterior, however the interior remains fresh. Petrography: (D. Sheikh, FSU) Sample is a diabase having a predominantly subophitic texture composed of complexly zoned, tabular and prismatic (sometimes twinned) chadacrysts of subcalcic augite and pigeonite (Av. 330±50 µm, up to 1mm, 60 vol%) contained within larger oikocrysts of maskelynite (Av. 800±100 µm, up to 2 mm, 40 vol%). Accessory phases include titanomagnetite (some Cr rich), ilmenite, silica, Si-Al-K-Na rich glass, merrillite, and pyrrhotite. Geochemistry: Subcalcic augite (Fs32.3±6.6 Wo30.7±2.3, range Fs21.7-47.7 Wo25.4-35.2, FeO/MnO=34±6, n=37) pigeonite (Fs52.7±8.5 Wo14.4±2.3, range Fs30.6-72.3 Wo10.0-19.3, FeO/MnO=36±4, n=54) maskelynite (An48.9±5.1 Or1.9±1.0, range An41.4-55.7 Or0.3-3.8, n=43). Classification: Martian (shergottite, diabasic) Silicate chemistry, the presence of maskelynite, FeO/MnO ratios of pyroxenes, and magnetic susceptibility provide support for classification as shergottite. Average grain sizes of pyroxenes and maskelynite larger than that of basaltic shergottites, but smaller than gabbroic shergottites, hence diabasic. Specimens: 10.02 grams at UCLA; main mass with Miguel Angel Contreras Gomez.
Name
*click on the Name for more information
Structure Class
achondrites
Chemical Class
Martian (shergottite)
Country
Year found
2020
Mass
346 g
[Museum Collection]
(1)20.529g (2)10.515g (3)4.461g (4)3.613g
(5)3.609g (6)3.178g (7)3.144g (8)2.531g
(9)2.445g (10)1.982g (11)1.860g (12)1.562g
(13)1.544g (14)1.468g (15)1.408g (16)1.399g
(17)1.288g (18)1.275g (19)1.260g (20)1.110g
(21)1.024g (22)0.879g (23)0.858g (24)0.853g
(25)0.795g (26)0.730g (27)0.717g (28)0.711g
(29)0.699g (30)0.608g (31)0.566g (32)0.517g
(33)0.497g (34)0.462g (35)0.451g (36)0.446g
(37)0.424g
History: Purchased by Eric Twelker in February 2020 from a Moroccan dealer at the Tucson Gem and Mineral Show. Petrography: (A. Irving, UWS and P. Carpenter, WUSL) Diabasic texture (mean grainsize ~0.8 mm). Composed predominantly of prismatic grains of zoned clinopyroxene and lath-like maskelynite together with accessory silica polymorph, merrillite, chlorapatite, Cr-Mn-bearing ulvöspinel, ilmenite, pyrrhotite and baddeleyite. Minor secondary calcite is present. Geochemistry: Subcalcic augite (Fs20.1-27.3Wo29.1-35.4, FeO/MnO = 19-34 , N = 5), ferroan subcalcic augite rim (Fs45.1Wo30.7, FeO/MnO = 36), ferroan pigeonite rims (Fs53.9-61.3Wo13.4-15.7, FeO/MnO = 36-37, N = 3), maskelynite (An53.4-55.7Or1.4-0.9, N = 4). Classification: Shergottite (diabasic). Specimens: 20.5 g plus one polished thin section at UWB; remainder with Mr. E. Twelker.
Name
*click on the Name for more information
Structure Class
achondrites
Chemical Class
Martian (shergottite)
Country
Year found
2020
Mass
249 g
[Museum Collection]
(1) 5.50g
History: Purchased from a Moroccan dealer in April 2020. Physical characteristics: Single stone, fusion crust, saw cuts reveals an ultramafic cumulate rock with ophitic to poikilitic textures with mm-size pale yellow and dark gray grains. Petrography: (C. Agee, UNM) Microprobe examination shows approximately 50% olivine, 40% pyroxene, and 10-5% maskelynite. Two distinct pyroxene trends are present 1) Mg-rich low calcium pyroxene trending to slightly more Fe-rich pigeonite, 2) Mg-rich augite trending to more Ca-rich augite. Ilmenite, spinel, Fe-sulfide, and merrillite are minor ubiquitous phases. Geochemistry: (C. Agee, UNM) Olivine Fa34.6±2.0, Fe/Mn=49±2, n=10; low Ca-pyroxene Fs22.5±0.5Wo4.7±0.7, Fe/Mn=29±2, n=6; augite Fs17.2±0.9Wo32.4±2.8, Fe/Mn=24±1, n=4; maskelynite An52.9±2.3Ab46.0±2.2Or1.1±0.2, n=4, fusion crust SiO2=46.5±0.6, TiO2=0.9±0.1, Al2O3=8.6±3.5, Cr2O3=0.7±0.1, MgO=18.0±3.5, FeO=15.3±0.5, MnO=0.4±0.1, Na2O=1.4±0.5 (all wt%), n=2. Classification: Martian peridotitic shergottite. Macroscopic textural appearance similar to NWA 1950 and ALHA77005. Paired with NWA 13250. Specimens: 20 g on deposit at UNM, Marcin Cimala holds the main mass.
Name
*click on the Name for more information
Structure Class
achondrites
Chemical Class
Martian (shergottite)
Country
Year found
2023
Mass
339 g
[Museum Collection]
(1) 5.25g (2) 2.57g
History: The meteorite was purchased from a meteorite dealer in Morocco. Physical characteristics: Grayish to dark greenish fragments with patches of black fusion crust. Petrography: The meteorite shows a poikilitic texture of up to 3 mm sized pyroxenes enclosing rounded to subrounded olivines that frequently contain trapped melt inclusions. Feldspar is a minor component and has completely been transformed to maskelynite. Accessory minerals include chomite, FeS and FeNiS. Contains glassy to finely recrystallized shock melt pocket. Geochemistry: olivine: Fa27.8±0.7 (Fa26.8-28.4, FeO/MnO=44±1, n=10); orthopyroxene: Fs18.7±0.3Wo2.4±0.1 (Fs18.3-19.5Wo2.3-2.6, FeO/MnO=27±2, n=10); pigeonite: Fs24.6±1.5Wo10.6±2.3 (Fs20.4-26.6Wo7.1-13.7, FeO/MnO=26±1, n=10); maskelynite (An53.2-56.3Ab42.4-45.4Or1.3-1.5, n=10) Classification: Martian meteorite (shergottite); likely paired with NWA 10961
Name
*click on the Name for more information
Structure Class
achondrites
Chemical Class
Martian (shergottite)
Country
Year found
2023
Mass
200 g
[Museum Collection]
(1) 2.21g (2) 1.54g
History: Purchased by Ruben Garcia from a Moroccan meteorite dealer. Physical characteristics: Sandblasted exterior lacking fusion crust. Broken surface reveals a mix of gray-brown pyroxene grains and shiny maskelynite grains. Petrography: (C. Agee and M. Spilde, UNM) The two major phases in this meteorite are clinopyroxene and maskelynite. Ubiquitous titanomagnetite was observed throughout. The clinopyroxene has a modal abundance of approximately 50%, with significant core to rim zoning observed in backscatter electron images indicating an igneous crystallization trend with Mg-rich augite and pigeonite cores, rimmed with ferropigeonite. Clinopyroxene average grain size is approximately 400-700 μm. Maskelynite has modal abundance of approximately 40%. Geochemistry: (M. Spilde, UNM) Clinopyroxene Fs46.2±15.0Wo25.5±7.5, Fe/Mn=37±4, n=36; maskelynite An53.9±2.0Ab45.2±2.0Or0.9±0.0, n=4. Classification: Evolved pyroxene-phyric basalt, clinopyroxene compositional zoning trends are similar to QUE 94201. Specimens: 20.2 g on deposit at UNM, Ruben Garcia holds the main mass.
Name
*click on the Name for more information
Structure Class
achondrites
Chemical Class
Martian (shergottite)
Country
Year found
2023
Mass
88.3 g
[Museum Collection]
(1) 1.534g
History: Purchased by Eric Twelker in January 2023 from a dealer in Guelmim, Morocco. Petrography: (A. Irving, UWS, and P. Carpenter, WUSL) The specimen has a relatively coarse grained intergranular texture and is composed predominantly of zoned, prismatic, simply-twinned grains of clinopyroxene (up to 3 mm long) and smaller laths of maskelynite (mean size ~ 1 mm). Accessory phases include merrillite, pyrrhotite, ulvöspinel, ilmenite and symplectitic intergrowths of fayalite+hedenbergite+silica polymorph (located at the margins of strongly zoned clinopyroxene grains). Small shock melt pockets containing "swirly" glass (pale clove-brown in thin section) are present, as well as some veinlets of secondary calcite and Fe oxides. Geochemistry: Augite cores (Fs22.0-25.7Wo45.7-40.4, FeO/MnO = 24-28, N = 4), ferropigeonite rims (Fs52.9-74.4Wo8.2-18.9, FeO/MnO = 34-37, N = 4), subcalcic augite rim (Fs60.1Fs21.1, FeO/MnO = 35), maskelynite (An50.1-54.9Or2.6-1.0, N = 4), fayalite in symplectite (Fa90.1, FeO/MnO = 40), hedenbergite in symplectite (Fs53.5Wo31.9, FeO/MnO = 35). Classification: Shergottite (gabbroic). Specimens: 18.1 g including one polished thin section at UWB; remainder with Twelker.