Abstract：
:Microscopic diamond was recently discovered in oxidized acid residues from several carbonaceous chondrite meteorites (for example, the C delta component of the Allende meteorite). Some of the reported properties of C delta seem in conflict with those expected of diamond. Here we present high spatial resolution analytical data which may help to explain such results. The C delta diamond is an extremely fine-grained (0.5-10 nm) single-phase material, but surface and interfacial carbon atoms, which may comprise as much as 25% of the total, impart an 'amorphous' character to some spectral data. These data support the proposed high-pressure conversion of amorphous carbon and graphite into diamonds due to grain-grain collisions in the interstellar medium although a low-pressure mechanism of formation cannot be ruled out.
journal_name
Naturejournal_title
Natureauthors
Blake DF,Freund F,Krishnan KF,Echer CJ,Shipp R,Bunch TE,Tielens AG,Lipari RJ,Hetherington CJ,Chang Sdoi
10.1038/332611a0keywords:
subject
Has Abstractpub_date
1988-04-14 00:00:00pages
611-3issue
6165eissn
0028-0836issn
1476-4687journal_volume
332pub_type
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