Cold Bokkeveld meteorite

An interesting application to the study of foreign bodies is the detection of iron in the Orgueil and cold Bokkeveld meteorites [117]. The former was shown to contain magnetite together with paramagnetic Fe + iron, possibly as a silicate. The latter did not contain the magnetic phase. 

Lee M. (1993) The petrography, mineralogy, and origins of calcium sulphate within the cold Bokkeveld CM carbonaceous chondrite. Meteoritics 28, 53-62. 

Sephton et al. (1998, 1999, 2000) used hydrous pyrolysis followed by supercritical extraction to examine insoluble organic matter in Orgueil (CIl), Murchison (CM2), and Cold Bokkeveld (CM2). The hydrous pyrolysates obtained for the three meteorites displayed a remarkable degree of qualitative similarity suggesting that the macro-molecular materials in different carbonaceous chondrites are apparently composed of essentially the same aromatic structural units, predominantly one to three ring alkyl-substituted aromatic structures. Significant quantitative differences were observed, however, and these were interpreted as indications of the different parent body histories of the three meteorites (Sephton et al., 2000). 

The GC-MS analyses of Murchison, Orgueil and Cold Bokkeveld macromolecular material indicate that the macromolecular materials in different meteorites are qualitatively veiy similar (e.g. made up of the same units) 11), In addition, oxygen-, sulfur- and nitrogen-containing moieties such as phenols, thiophenes and benzonitrile have also been detected in the pyrolysates. The H2-pyrolysis further demonstrated that the refractory component probably consists of a network dominated by at least five- or six-ring PAH units that are crosslinked together 13). 

Although the macromolecular material has been found to be qualitatively very similar between the Murchison, Cold Bokkeveld and Orgueil meteorites variations in the ratios between one-ring aromatic hydrocarbons (benzene and alkylated derivaties), two-ring aromatic hydrocarbons and phenols exist between these meteorites (//). Phenol abundances increase in the order Orgueil < Cold Bokkeveld < Murchison, while the one-ring aromatic compounds show the opposite trend. These characteristics may be explained by the effect of aqueous... 

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