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Cliftonite in meteorites: A proposed origin

R. Brett·G.T. Higgins
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Abstract

Cliftonite, a polycrystalline aggregate of graphite with cubic morphology, is known in ten meteorites. Some workers have considered it to be a pseudomorph after diamond, and have used the proposed diamond ancestry as evidence of a meteoritic parent body of at least lunar dimensions. We have synthesized cliftonite in Fe-Ni-C alloys in vacuum, as a product of decomposition of cohenite [(Fe,Ni) 3 C]. We therefore suggest that a high pressure origin is unnecessary for meteorites which contain cliftonite, and that these meteorites were formed at low pressures. This conclusion is in agreement with other recent evidence.

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R. Brett, G.T. Higgins. 1967. Cliftonite in meteorites: A proposed origin. https://doi.org/10.1126/science.156.3776.819

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