Diogenites
Name
*click on the Name for more information
Structure Class
HED achondrites
Chemical Class
Diogenite
Country
Burkina Faso
Year found
1999
Mass
25 kg
[Museum Collection]
(1) 48g (2) 41g
After a widely witnessed shower, at least 25 kg of meteorites with fresh black fusion crust were collected, comprising many stones. Pieces are reported to have fallen in the villages of Bilanga-Yanga and Gomponsago (coordinates above apply to the latter). Classification and mineralogy (A. Bischoff, Mün): a diogenitic breccia; Ca-poor pyroxene, Fs19–22, mean Fs20.5; plagioclase, An75–83; Ca-rich pyroxene is rare, one grain has En46.4Fs6.3Wo47.4. Oxygen isotopes (R. Clayton, UChi): δ18O = +3.41‰, δ17O = +1.35‰. Specimens: 7.5 kg, Casper; 4 kg, Heinlein; type specimen, 8 g, Mün; 25 g, NHM; 20 g, TCU; 80 g, Frei; 600 g, SI.
Name
*click on the Name for more information
Structure Class
HED achondrites
Chemical Class
Diogenite
Country
Oman
Year found
2002
Mass
2.77 kg
[Museum Collection]
(1) 2.54g
Twelve dark-grey stones totalling 2770 g were found in the Dhofar region of Oman. Classification and mineralogy (S. Demidova, Vernad; G. Kurat, NHMV): fusion crust is absent. The meteorite has an equigranular texture, and consists dominantly of orthopyroxene (Wo2.5–7En62–71; Fe/Mn ≈ 25 at.). Accessory minerals are clinopyroxene Wo8–25En55–66, olivine Fo63–68, plagioclase An89–95, silica, chromite, troilite and FeNi metal (0.2–3.8 wt% Ni, 0.3–0.8 wt% Co); terrestrial weathering is not significant; rare Fe hydroxide is present. The mafic silicates in Dho 700 have the low mg# that is a characteristic feature of diogenites. Specimens: 350 g plus thin section, Vernad; main mass with anonymous finder.
Name
*click on the Name for more information
Structure Class
HED achondrites
Chemical Class
Diogenite-pm
Country
(Northwest Africa)
Year found
2007
Mass
175 g
[Museum Collection]
(1) 18.7g (2) 13.7g (3) 11.3g (4) 2.7g
(5) 2.62g
History: Purchased by Twelker in 2007 September from a Moroccan dealer at the Denver Mineral Show. Petrography: (A. Irving and S. Kuehner, UWS) Very fresh fragmental breccia consisting predominantly of angular diogenitic orthopyroxene grains (up to 2 mm across) plus
Name
*click on the Name for more information
Structure Class
HED achondrites
Chemical Class
Diogenite-pm
Country
(Northwest Africa)
Year found
2017
Mass
784 g
[Museum Collection]
(1) 28.0g (2) 4.5g (3) 4.4g (4) 3.9g
History: Purchased by Eric Twelker in May 2017 from a Moroccan dealer. Petrography: (A. Irving and S. Kuehner, UWS) Breccia composed of angular mineral grains and rare pyroxene-chromite symplectite clasts in a sparse matrix. The predominant mineral is low-Ca pyroxene (exhibiting undulose extinction) with subordinate olivine (of several different compositions), chromite, metal, fayalite, and minor (
Name
*click on the Name for more information
Structure Class
HED achondrites
Chemical Class
Diogenite
Country
(Northwest Africa)
Year found
2022
Mass
670 g
[Museum Collection]
(1) 5.50g
History: The meteorite was purchased from a meteorite dealer in Morocco. Physical characteristics: Light grayish rock without fusion crust. Petrography: The meteorite displays an unbrecciated grayish interior and is predominantly composed of up to 5 mm sized interlocking orthopyroxene (56 vol%) and calcic plagioclase (42 vol%) grains with minor Ti-bearing chromite and troilite. Few orthopyroxenes contain blebby augite exsolutions. Geochemistry: low-Ca pyroxene: Fs30.8±0.2Wo3.4±0.4 (Fs30.4-31.2Wo2.6-3.9, FeO/MnO=24-26, n=12); Ca-pyroxene: Fs15.9±0.4Wo39.7±0.4 (Fs15.5-16.6Wo39.1-40.1, FeO/MnO=19-20, n=6); calcic plagioclase: An96.1±0.3 (An96.0-96.5, n=11) Classification: Diogenite (noritic). Anomalous high plagioclase abundance (42 vol%).