Cloppenburg meteorite (H4-5, S3, W3) registered in Meteoritical Bulletin database
Update (18 October 2017):
Photo of the uncut ‘Cloppenburg’ meteorite (8 x 5 cm) found by Hartmut Osterburg
(Photo: D. Heinlein / Münsterländische Tageszeitung, 19 August 2017)
Rarität aus dem All am Feldrand entdeckt (PDF)
(Sonntagsblatt f. d. Landkreis Cloppenburg, 19-20 August 2017)
„Cloppenburg“ direkt aus dem Weltall
(nwzonline, 19 August 2017)
Find: 15 March 2017
Classification: Ordinary chondrite (H4-5)
History: (D. Heinlein) The rock was found by the facility manager of a school while collecting rocks for the school garden, lying on a rock pile next to a potato field. The stone was kept by the finder, because of its unusual appearance and its magnetic properties.
Physical characteristics: D. Heinlein and A. Bischoff, IfP: The sample has a total mass of 141 g. Two slices were cut from the piece and some material was removed for bulk chemical analysis. From the remaining type specimen of 20.5 g, three polished thin sections were prepared. The actual main mass of 117.6 g has a density of 3.33±0.03 g/cm3. The fusion crust is absent due to weathering.
Petrography: S. Ebert, J. Storz, A. Bischoff, IfP: The meteorite is heavily weathered (W3). The remaining metal grains have thick rims of terrestrial alteration products (Fe-oxides and -hydroxides). The rock is a breccia containing fragments of petrologic type 4 and 5. The planar fractures in olivine indicate that the breccia is weakly shocked (S3); shock veins are also present. The occurrence of vivianite indicates that the sample was weathered in a very wet environment consistent with the find location in Lower Saxony having abundant moors.
Geochemistry: Mineral compositions and geochemistry: S. Ebert and J. Storz: The mean composition of olivine is Fa18.5±0.3 with a compositional range of Fa17.7-19.1 (n=34). The low-Ca pyroxenes have a mean composition of Fs16.4±0.6 (n= 31) with a range of Fs15.6-20.6.
Specimens: Type specimen: IfP; main mass of 117.6 g with Heinlein.”